For me it is the SQ. My reissue MC75s were clearly superior to either my single and especially to my pair of MC275s running as monoblocks (a single MC275 sounds better to my ears in my system). The fact the MC75 is much lighter is a real bonus. But, it is the SQ that matters most.
I didn't sell it by choice. I was restoring an old house and needed extra money so I sold my entire stereo system to help with the funds. By the time I once again had enough extra funds to replace my McIntosh system, the MA2275 was not longer in production. I looked for a used one, but the MA2275 eluded me and I could not find one. I gave up and ended up going a different route. I have more recently seen some used examples come up, but they were not in a condition that was acceptable to me. Now, the MA2275 is starting to get old so getting a used one in mint condition is nearly impossible without paying a super high premium. This is why I was hoping they would replace it, which now they have, but like I said, the new MC275 chassis inspired designs for integrated amps in my opinion, is super ugly. To each their own.
That wasn't my experience at all with the MA2275, I loved the sound of it. See my comment above as to why I had to sell it, it wasn't by choice. I also didn't at the time have room for separates like I do now so the MA2275 was a better choice for me than a C22 and an MC275.
You never know. The MA252 is an excellent integrated amp that's for sure. I had one in my home office and loved it. It weighs 28lbs. The 2375 95 pounds. My 601 mono blocks 93 lbs.
