This is MY ears opinion only. I find McIntosh very dry and muffled on the Summit and CLX that I heard.
The CLX I heard when ML was doing tour around the country. The well treated room at a dealer in Raleigh NC was set up by ML. I was fortunate enough to have over an hour in the room to my self listening to a variety of music. The music just didn't have the open crispness that other amps have had.
I used Mac amps for years with my horn speakers and loved the sound.
I have heard ML's with CJ amps and ARC in my system for a number of years. I am a fan of ARC sound and I understand not everyone likes it. Just my .02.
Same disclaimer as above -- this is to MY ears: Hearing 15A's run off of MC2301 tube mono's is what made me fall in love with ML's and McIntosh. But I will say in my experience not all McIntosh amps are a good match for ML panels. I'm currently using a McIntosh MA352 hybrid tube integrated with my 11A's. Sounds good, but not great. The MA352 is a direct coupled design that does not use the typical McIntosh autoformers. IME, that makes a difference. I demo'd the MC462 2-channel with my 11A's and that was it. That was the sound. Much more open, the harshness in the mids gone, nice top end sparkle. Placed an order with my dealer. And now I wait...