I lost a lot of my time looking for a place in the SanDisk website where I can see the speeds of each Sandisk Pendrive.
It seems this information it’s not published in any place and looking for the messages on this forum it seems they have a poor read/write speeds.
The only thing I found it’s the Ultra and Extreme pendrives has a speed from 10Mb/s to 25Mb/s, without any read or write remark of these values. http://kb.sandisk.com/app/answers/detail/a_id/7491/~/sandisk-products-transfer-speed
I think it’s a very poor information about the most important key of an USB Memory, and a big buy-stopper.