Just to toss a different opinion into the mix. I have listened to the McIntosh MC275 in my system, but not with the Harbeth. The MC275 is an excellent unit with good slam but not exactly the last word when it comes to transparency and dynamics. The dynamics of the Compact 7ES-3 will come alive with the LFD Zero MkIII integrated. Compared to my other amps which include the Plinius and NVA to name a few, the LFD made all these amps sound lacklustre, shut-in and lacking in the dynamics department. The LFD made music come alive especially with rock music with its excellent speed, tonal accuracy and bass slam. At least that is what I have experienced in my system.
Of course, there are other speakers that will be even more dynamic and transparent, and that I cannot deny. However, resolution and transparency sometimes come at a cost. Too much of it can translate to higher listening fatigue. To each his own.