I own a PSP, digital camera and PDA and, as such, use SD cards, memory stick pro duos and compact flash cartridges. I had originally read a few reviews of this product from amazon.co.uk and was slightly put off by the one or two bad experiences people were having with it but now, after having tried it myself, I can say that it's absolutely brilliant.
Plug it in and wham, four new drives appear without any installation required (I thought it wasn't working at first as I didn't receive any system messages regarding new hardware found). This truly is "plug and play", right now I have 3 cards in it and they're all reading perfectly. I'm sure that if you have a PDA you're already familiar with how long it takes active sync to transfer large files to a CF card (as well as how unreliable the process is), this little gadget speeds it up by 100% and it works perfectly every time.
It really is a perfect little wonder. 5/5 A++