Dana,
On the issue of problems with Viking and SimpleTech and, actually, any major manufacturer of cards, or cameras for that matter: Within this forum alone, I've seen several threads where people report on the problems they've had with their G3's. And over at dpreview, I think, there was a report of the CCD(?) being misaligned on "bunches" of G3's causing photos to print lop-sided. And if you've bought your camera in the last few weeks you should check it for this problem. (To my knowledge, Canon has not addressed this issue to the public.)
Interestingly, at www.imaging-resource.com/PRODS/G3P.HTM
, they use a SimpleTech 512 to demonstrate for the section on Image Storage and Interface. At www.d-store.com/d-store/product/cfspeed2.htm
, Sandisk was one that came in last place for speed and Viking was one of the highest performers.
There are probably a gazillion or two flash cards out there. The major manufacturers have been in business for many years now--competition is fierce, I'm sure. None of these manufacturers can afford to put out bad product. And so long as manufacturers are willing to stand behind their products, can we expect more?
OK, OK, I'm a little sensitive. 
cedar