| 1: Intro & spec | 2: First impressions | 3: Installing an HDD | 4: User interface | 5: Timings & performance | 6: Compared to | 7: Conclusion |
Nexto CF Ultra ND2525
portable storage device review
5: Timings and performance
Note: All Tests performed using a Toshiba 120Gb MK1234GAX. For maximum performance NextoDI UK recommended an HGST drive, however in my experience HGST drives have proven very unreliable in the past; as this device is intended to store my photographs, it wasn't a risk I was prepared to take. Hard disk reliability is paramount for storing your images though, particularly if you're only carrying one device. I use two, the Nexto with a 120Gb Toshiba HDD, and the PD70X with a Western Digital 100Gb HDD to minimize the risk of failure.
Often the prudent option is to buy drives which have been on the market for at least six months; as failure rates become known by that point. Unfortunately that also means you'll be buying older technology, which means slightly slower and slightly smaller capacities.
Autonomy test results
The key performance feature of any portable storage solution has to be how much data it can transfer between charges. There are three factors at play here, battery capacity, transfer speed, and low power consumption.
In this test the Nexto CF Ultra ND2525 managed to copy and verify 45.4Gb on one charge, which is very impressive indeed. In fact it managed to transfer another full 4Gb card after that, but unfortunately it ran out of power during the verify phase, so I've disqualified that transfer. The good news is that it failed gracefully, displaying a low battery warning very briefly before shutting down - no data corruption.
Test specs: Both batteries, full verify, card: Sandisk Ultra II 4Gb,
Nexto fitted with Toshiba MK1234GAX, ambient temp 20°C
Card to HD transfer rates
From the table above we can see the average transfer rate from the card to HDD is 10.9Mb/s. A very good result indeed, very close to the maximum performance possible from the Sandisk Ultra II used in testing.
For comparison purposes, I also ran a copy using a 2Gb Sandisk Extreme IV. The faster card showed much higher transfer rates (15.7Mb/s), although nowhere near the maximum performance possible with the card:
Test specs: 2Gb Sandisk Extreme IV,
Nexto fitted with Toshiba MK1234GAX, ambient temp 20°C
Small files vs large files
This test is to see whether the copy speed is significantly affected by the number of files, and/or filesizes used. This should give a good indication whether the device can handle the relatively small JPEG files often produced by compact cameras, or whether it's only suitable for large RAW files. Good news here too, the Nexto handles both with equal aplomb - although there's slight variation, it's reasonable considering the total amount of data transferred was slightly different in both cases.
Test specs: Sandisk 256Mb Ultra II,
Nexto fitted with Toshiba MK1234GAX, ambient temp 20°C
Computer transfer rates
Obviously high speed transfers from memory card to the Nexto are the most important aspect, but how does it perform when the time comes to copy the data on the hard disk back to the computer? Again testing showed another respectable result:
Test specs: OS, Windows Vista Ultimate. Hardware, 3.6GHz P4, 1Gb
DDR3200. AVG anti-virus, Windows Defender and Spybot S&D.
IEEE1394 connnection. Data, 49.2Gb image files (the large RAW files
from the autonomy test).
The torture test
How does the device cope when the unexpected happens? As mentioned above when the batteries are too flat, the device shuts down cleanly. But what happens when the memory card is suddenly removed during a transfer? Pulling a card out causes the Nexto to invalidate the directory for that transfer, but all other data remains unharmed. The first failed directory is called tmp.000, and can be deleted from the device itself, or the PC. Reinsertion of the same card will start a new directory as usual, and the whole card is copied normally.
5: Timings and performance
Note: All Tests performed using a Toshiba 120Gb MK1234GAX. For maximum performance NextoDI UK recommended an HGST drive, however in my experience HGST drives have proven very unreliable in the past; as this device is intended to store my photographs, it wasn't a risk I was prepared to take. Hard disk reliability is paramount for storing your images though, particularly if you're only carrying one device. I use two, the Nexto with a 120Gb Toshiba HDD, and the PD70X with a Western Digital 100Gb HDD to minimize the risk of failure.
Often the prudent option is to buy drives which have been on the market for at least six months; as failure rates become known by that point. Unfortunately that also means you'll be buying older technology, which means slightly slower and slightly smaller capacities.
Autonomy test results
The key performance feature of any portable storage solution has to be how much data it can transfer between charges. There are three factors at play here, battery capacity, transfer speed, and low power consumption.
In this test the Nexto CF Ultra ND2525 managed to copy and verify 45.4Gb on one charge, which is very impressive indeed. In fact it managed to transfer another full 4Gb card after that, but unfortunately it ran out of power during the verify phase, so I've disqualified that transfer. The good news is that it failed gracefully, displaying a low battery warning very briefly before shutting down - no data corruption.
| Test # | Time, copy | Time, full verify | Data transferred | # Files | Notes |
| 1 | 5m45s | 8m10s | 3.77Gb |
335 |
Fully charged |
| 2 | 5m47s | 8m10s | 3.77Gb | 335 | |
| 3 | 5m47s | 8m10s | 3.77Gb | 335 | |
| 4 | 5m46s | 8m10s | 3.77Gb | 335 | |
| 5 | 5m48s | 8m10s | 3.78Gb | 335 | |
| 6 | 5m49s | 8m12s | 3.79Gb | 336 | |
| 7 | 5m48s | 8m12s | 3.79Gb | 336 | |
| 8 | 5m48s | 8m11s | 3.79Gb | 335 | |
| 9 | 5m49s | 8m12s | 3.79Gb | 335 | |
| 10 | 5m46s | 8m11s | 3.79Gb | 335 | Battery indicator half full during copy phase |
| 11 | 5m47s | 8m12s | 3.79Gb | 334 | |
| 12 | 5m48s | 8m45s | 3.78Gb | 333 | Battery indicator shows empty during verify |
| 13 | 5m49s | n/a | 3.79Gb | 333 | Verify failed due to insufficient power |
Card to HD transfer rates
From the table above we can see the average transfer rate from the card to HDD is 10.9Mb/s. A very good result indeed, very close to the maximum performance possible from the Sandisk Ultra II used in testing.
For comparison purposes, I also ran a copy using a 2Gb Sandisk Extreme IV. The faster card showed much higher transfer rates (15.7Mb/s), although nowhere near the maximum performance possible with the card:
| Time, copy | Time, full verify | File details |
| 1m57s | 3m14s | 187 Large RAW files, 1.8Gb total |
Small files vs large files
This test is to see whether the copy speed is significantly affected by the number of files, and/or filesizes used. This should give a good indication whether the device can handle the relatively small JPEG files often produced by compact cameras, or whether it's only suitable for large RAW files. Good news here too, the Nexto handles both with equal aplomb - although there's slight variation, it's reasonable considering the total amount of data transferred was slightly different in both cases.
| Time, copy | Time, full verify | File details |
| 24s | 31s | 257 small JPEG files, 234Mb total |
| 20s | 28s | 19 large RAW files, 224Mb total |
Computer transfer rates
Obviously high speed transfers from memory card to the Nexto are the most important aspect, but how does it perform when the time comes to copy the data on the hard disk back to the computer? Again testing showed another respectable result:
| Read | 22Mb/s |
| Write | 17.3Mb/s |
The torture test
How does the device cope when the unexpected happens? As mentioned above when the batteries are too flat, the device shuts down cleanly. But what happens when the memory card is suddenly removed during a transfer? Pulling a card out causes the Nexto to invalidate the directory for that transfer, but all other data remains unharmed. The first failed directory is called tmp.000, and can be deleted from the device itself, or the PC. Reinsertion of the same card will start a new directory as usual, and the whole card is copied normally.
This review contains the opinions of the author, which are subjective. All technical data is believed accurate at time of publication, however please check it with the manufacturer before making a purchasing decision. I hope you enjoy my site, and if there's anything you feel could be improved, please drop me a line at: 
All images/text/content © Adrian J Warren 2007.
All images/text/content © Adrian J Warren 2007.