Thanks for responding. I've been enjoying this hobby so far an I think I've hit a nice level where I am satisfied for a while. I have to fit this hobby in with my other hobbies. Besides audio I'm also a bit of a gear head and am building two different cars for road racing and autocross (yay old Z's and toyotas). I'm glad I don't have any audiophile friends with better systems otherwise I might feel a stronger need to upgrade-- though browsing this site doesn't help with that :)
I've had the opportunity to listen to some tube amps at work and really liked the difference in sound. There was a Jolida 502 amp with upgraded tubes I could have bought for around $450 that I kind of wish I had snagged. I may get a smaller tube amp and setup a second system in my bedroom.
I could use my m290is speakers for that system since they really are wasted right now doing rear surround duty on my main system. They're pretty sensitive at 90db. For a while I had them hooked to that Sharp 1-bit amp/receiver. The Sharp is 25wpc at 4 ohms, so at 8ohms it's probably only 15-20wpc. Even with that low power the Mirage m290is's sounded pretty good.
I'm keeping my eye out for a good tube amp with maybe 25-50wpc. Any suggestions?