Now that I have had the Salk ss8s for a year, I am on the hunt for some replacements of my aging. Bryston SP1.7 processor as a dedicated 2 channel preamp. Mcintosh sounds like it's working nicely in your system. I may need to look into them. I was looking mostly at Bryston maybe BAT now maybe Mcintosh!
Well... I'm not one to tell what "should" sound better as I've heard so many good combinations that I could have easily bought something else. The reason for choosing McIntosh was as much heart than brain as it was the first brand with which I litterally fell in love as a kid so it's some kind of a dream come true. And listening to Nina Simone's "Little Girl Blue" in high resolution FLAC files just now (with the MC275) comforts me in the fact that "this" combination works "for me".
I know many people say many things about McIntosh and you often read comments saying that the sound is "veiled" but I just don't see (or rather "hear") that. Maybe it's what I call "forgiving" or "none-fatiguing", I don't know. All I know is that, for my taste and in my experience, if all components are so-called "revealing" and "full of details", most of the time, I'll end up feeling it all sounds "harsh" or "fatiguing".
So, what I can tell you is that, for my taste, the C2200 preamplifier works incredibly well with either the MC275 or the MC501s. Some people will prefer the C2300 (try to hear both, if you can) but having owned (or still owning) different McIntosh preamps (or tuner/preamps), I was never disapointed and probably could have lived with the MX110 were it not for its limited number of inputs and, to a certain extent, the lack of XLR connection. The C2200 was my favored option for many reasons, within the budget I had and I do not regret it, especially now that my Veracity STs have had time to clear their throats and all cables have had proper burn-in time etc, etc.
I guess my conclusion is : don't discard McIntosh from your serious contenders' list !