I bought one of these for use to increase the cache memory on my netbook. Windows Readyboost sectioned 4gb for cache and there is 12gb left for storage. I leave it in the drive permanently and it definitely increases the speed of my netbook. I would love to do the same on my desktop but am running that on XP which does not have Readyboost (need Vista or Windows 7). I have not tested it for file transfers and cannot comment on speeds but it is well worth the price for the purpose I bought it for.