Mac MA 352 vs Pass INT-60

About a year ago, I purchased an INT-60 and drove one of the not-easy speakers (Sonus Faber Electa Amator v.1) with 4 ohms and not a pair of high-sensitive speakers. It has been doing great, and I enjoy the music coming out. With the meter on INT-60, it hardly gets into the AB zone until I play music with a lot of bass and loud. 

Build quality is as good as my old ML #20. 

First off, I’m a McIntosh fan. All my gear minus streamer and turntable are Mac. That said, I owned the MA352 for about 6 months and quickly moved on. Wasn’t for me. Found the top end a bit harsh and fatiguing. Note that’s it’s a hybrid. Tube front end, SS power amp.

Thanks folks for the input,  which kind of solidified the way I was leaning (toward the Pass). Surprisingly was able to get a new one for around $7500.  I wanted the tube/SS combo deal on the Mac as that was my initial consideration, plus the balance control that I finally realized I didn't need (I had another equipment problem I fixed).  Input from you and others convinced me I could get the warmth out of the INT-60, and the backlog and lack of info on the Mac started to bother me, along with some uncertainties some have had about their service facilities and support, not to mention the ownership change. Probably not to worry, but no problems there for sure with Pass, although was surprised no dealer in Houston area (or Texas)..  One other thing you may have an opinion about: heat management.  My rack has a space just big enough for the amp but is completely open front and back.  I could put it on top but am concerned that might be getting top-heavy up there.  I'm putting a maple platform under it as its feet are an inch or so farther apart than my 15 inch support.  Upgrading has put me into a league that I have to have my son lug the equipment for me!  Times change!  Thanks for the help.  

Yes, the pass 60 is heavy, but the 250 is heavier. It weighs 106 pounds! I have a small two-shelf rack and put my pass on the top level. I use a hydraulic lift to take it down and put it up. I'm 70, and no way can I lift that beast. Enjoy your Pass, it is a great-sounding amp. The 250 leans a bit more to the neutral side with a hint of warmth. What the 250 has over the 60 is treble refinement.

@OP The Pass is a much better sounding amp than the Mac and I hope you will be very happy with it. Most of the heat it generates is via the heatsinks but you really should have a couple of inches at least of air circulation space above the top plate. So it would be better on the top of your rack. Unless your rack is not level, the amp the load of the amp is compression only so there are really no concerns there.