I got this card from BestBuy about 4 months ago (during a brief sale for $99) and have not had any real problems.
The only issue - but it is kind of a big one - is it's tricky for Music Apps to find my songs. And occasionally, perhaps after a fresh reboot or draining the battery, it will "forget" the music. The work around I discovered was going into file manager and renaming the music folder (and then back) and then it will search and find music. Smaller music folders didn't fix it.
Now I just recently upgraded to Scotts Cleanrom Pro. Had been running stock GB this entire time. Also only tried stock HTC music app and Tunewikki.
So I've not really put it thru its paces (camera stores pics on the internal card). It definitely works, and if the comparison is swapping SD cards then occasionally having to find your music again is a pretty decent trade-off.