Looking for great Amp for Martin Logan Prodigy woofers

I am rebuilding my audio system; centered around getting the most out of the Martin Logan Prodigy.  I have Audio Research VT 100 (intended to drive the panel section).  Now I am looking for a second amp (stereo or Mono blocks) to drive the low end.  I've seen a lot of people using McIntosh, but I am not going that way.  I want a used, well-built and rugged, yet musical amp, (like the Krell FPB 300).  The budget is $2.5k  Does anyone think Krell is the way to go? Suggestions please.
Thank you