I never had a HM-2
so I suppose you mean the MT-2
I didn't replace it. That first set of 4 Boss pedals was used with a single channer transistor amp, so I needed distortion from a pedal.
Then I bought a Hughes & Kettner Vortex half stack as a temporary amp, and last year I bought a Hughes & Kettner Triamp + H&K greenbacks cab, that one stays!
My pedals right now: EHX Big Muff (fuzz/overdrive), Dunlop Crybaby (wah), Line 6 DL-4 (delay/loops), Boss DD-6 (delay), EHX Holy Grail (reverb), Rocktron Nitro (booster), Boss TU-2 (tuner), and then my H&K floorboard