I'm very happy with my 2002 MC275 MK IV, it has better OTs than the Commemorative model before it, plus the classic speaker binding posts. It sounds wonderful, even if it is built on a PCB and not point to point. The biggest technical difference to the MK VI is that the feedback loop on my MKIV is in front of the OT, so it's classic. The MK VI has the feedback loop behind the OTs. Ron C, a longtime Mcintosh employee had explained this in another forum. Supposedly this produces a better damping factor. I haven't heard it yet, according to reviews it sounds "cleaner" stronger bass etc.. But I really like the classic sound of my MC275 MKIV very much.