I shot many hours on my transcend cards this winter in Montana and never had an issue. They have always been rock solid. I have both CF and SDHC Transcend cards. I like this brand and have stayed loyal to them since 2007. No issues at all so far.
I recently had issues with some Transcend cards I picked up on eBay. Turned out to be forgeries. Fortunately the seller refunded me and was shocked to learn they weren't legit. They were the 32GB Class 10 cards. Be careful and only buy from a reputable source. If the price seems too good to be true.....
I like Transcend cards. Good price/gb and lifetime warranty. However, just like hard drives, it's not a question of if a memory card will fail, but when. Though I have yet to have a corrupted Transcend card myself, I would highly recommend bringing several cards with you to any shoot so that you can at least keep on shooting even if a card does fail.
I had one failure in a 8GB card bought 4 months ago. Of course, at their price point, they're practically consumables, so I'm not too bent out of shape about it.
Several reports of transcend failures in the hmc 150 area in the past. I shot several hundred kingston cards in the past until I had a failure. I only buy panasonic gold or lexar professional now.