I've had two Crucial Gizmo's now and they are brilliant. One I've had for about 5-6 years, the other I bought about two years ago because 128mb wasn't enough, so i opted for a 4 Gb.
Ordered both direct from crucial at very competitive prices, with just standard delivery and they came next day.
When i was at college a lot of people bought cheap rubbishy ones and they broke or randomly corrupted data but both me and two of my friends had no troubles at all with the Crucial's apart from one being stolen.