— The 64GB SanDisk Ultra Fit is the largest capacity available in the Ultra Fit range. Both the 16GB and 32GB siblings fared well in terms of peak performance but with the majority of flash based products larger capacities are faster. Unfortunately for the Ultra Fit this proved not to be the case. Comparing the performance leading Mushkin Ventura and 64GB Ultra Fit shows that the Ventura is around 600% faster but just 60% more expensive. Although the Ultra Fit is a contender in the 32GB and 16GB capacities it doesn't fare well against the 64GB competition. If you are looking for a tiny form factor the 64GB SanDisk Ultra Fit is superb but otherwise there are better alternatives available with better peak and significantly better sustained transfer speeds.

— The 32GB Sandisk Ultra Fit has both a tiny form factor and a respectable performance profile. With peak sequential read/write speeds of 136/55 MBps and peak 4K read/writes of 6.6/2.0 MBps the 32GB Ultra Fit sits amongst the top 25% of 32GB flash drives. In terms of value for money the Ultra fit fares even better and is bested only by the Sandisk Extreme. Comparing the 32GB Extreme and Ultra Fit shows that the Extreme has over double the effective speed yet the extreme is only 32% more expensive than the Ultra Fit. To conclude, the 32GB Ultra Fit has good peak performance (sustained performance is far less impressive) but its key strengths are its tiny form factor and reasonable price tag.

— The 16GB SanDisk Ultra Fit USB 3.0 is a remarkable flash drive. As well as packing a tiny form factor, the Ultra fit also boasts an impressive peak performance profile with maximum sequential read/writes of 129/46 MBps and 4K read/writes of 6.08/1.51 MBps. The Ultra Fit is actually only bested by three other 16GB models (Sandisk Extreme, Lexar P10, Lexar Triton) all of which cost between from 60-230% more. In terms of outright performance there are better alternatives but in terms of value for money the Ultra Fit is hard to beat. The superbly low price coupled with an amazing form factor which is barely larger than a USB socket make it easy to recommend the 16GB Ultra fit as the best small form factor flash drive on the market. The only thing to watch with the Ultra Fit are its sustained speeds which are significantly lower than peak.

— The Kingston DataTraveler Rubber G2 has a robust (water/shock resistant) form factor and an above average performance profile for a 32GB flash drive. Comparing the performance of the G2 and G1 shows that peak speeds are largely unchanged but average user speeds are significantly faster on the newer G2. We only have three samples of the 32GB G2 at present so we can't form a strong opinion yet. In terms of pricing the G2 is reasonable and is thus currently ranked 8th/27 in the 32GB group test. We will update this review when we have more performance samples.