GTShadow has been one of the best performers on the site. It's really the same as RoboMiner, but with more advanced settings, so it should be used only by advanced traders. It's more advanced than I know how to use (or care to use, more aptly) but it can be very powerful. I know a few people doing some crazy things with it and making good profits.
As far as worthless, I guess if doubling your money in a year makes it worthless ...
I'd love to get some discussion going about the best settings, but so far everyone has been pretty secretive about getting the best setup!