Another one worth considering is the PNY USB3 256GB flash drive on 7Dayshop, which also has a 2 year warranty. It's £24 delivered shipped from Guernsey. I ordered it last Sunday and it came on Wednesday.
It's rated at 20MB write and 80MB read, although the one I ordered reads a lot faster.
Average write speed, after copying about 27GB to it:
1549.408MB/min = 25.8MB/s
Average read speed, after ejecting it and plugging it back in:
12260.87MB/min = 204.3MB/s
After seeing how quickly it read those files, I wondered if it had some files cached. So I did a quick copy of a 3.8GB ISO file that was placed earlier on the stick back to the PC: