We just launched our site PennyVacay.com on July 1st after doing months and months of the exact reasons bidders like you gave it all up. Now that these sites have come into their adolescence, its clear what works and what doesn't.
We are hoping we have developed a system that has more control over the disadvantages for users and immoral business practices. We have a rewards system that keeps users of a certain skill level within certain auctions. The new users can go against one another, and the skilled can go against one another. Sites that don't pay out what they promise is the worst of all and usually happens when these sites go bankrupt (usually because they didn't do their math correct and started hemorrhaging money). We are starting small and scaling appropriately so that never happens to us. If we were to ever shut down we are also legally obligated to pay out any remaining outstanding auctions.
Eventually our business model will kick in delivering vacation, hotel and cruise deals as auctions, sending people on vacation for a huge discount.
I hope you'll give us a shot, even if its for old times sake. If not, thanks for steering this industry more into legitimacy. 