Peavey Rockmaster
it's not programmable but has 3 channels, it's very affordable, and kicks all sorts of ass. mine broke down a few years ago, but it was definitely capable of a modern metal tones as well as decent crunch and cleans. the lead channel is supposed to be based on the peavey ultra
it has FX loops for each channel as well as as common loop for all channel or only the gain ones. you could also get it to switch channel with a cheap midi switcher since the whole preamp is operated by one stereo footswitch. even a g-major could switch channels for you ;-)