lomb,
There are several points throughout this thread that i will make comments to, but as for your review, i thought it was quite good. By providing all the details under which you auditioned the speakers, other readers can gauge their opinions accordingly in whatever light they view your circumstances (e.g. hard walled room, smaller room, high quality receiver used, or ....etc.).
The one thing you had not mentioned and i'm curious about, was if you had setup the speakers for equivalent SPL during your listening. The difference in SPL could account for lost bass or extraordinary highs along with many other possibilities perceived as differences b/w the units.

I did notice that one of your test songs was The Sundays-Summertime. I've long suspected this particular cd was recorded 'hot'. I actually put that very song on my test disc as the one song that had such a blaring opening that it could easily distinguish 'forward' speakers from laid back models. It is indeed a piercing song when played with bright (or detailed) speakers and similar recordings will no doubt cause listening fatigue. The Sundays cd is a great example of how one's recorded music may dictate the type of speaker they would be happier buying.

As for the concern about the 750s vs the M60s instead of the M80s, price is moot and always should be in a comparison. One does not need to pair the top of the line anything against another brand top of the line. Both sets of speakers are floorstanding and that is about as far as one can go to match up speakers. Each model may have different driver numbers, crossovers, cabinet materials, bracing, weights, etc. so exactly matching anything is near impossible.
Obviously $$ do not matter as they do not equate to quality. The M80s will play louder with a slightly greater bass extension than the M60s but are otherwise equivalent. I've read many times how a reviewer looks at Axiom speakers, pairs them against say some B&W 703s, states how Axiom fares very well but the B&W still win out, but hey, B&W also costs $3k more so it is expected.
I say bunk to that. If those reviewers were blind tested w/o knowing brand or cost, i think such statements would disappear from such reviews.

Again, your post was a great look at the Rockets. I've never heard them but am quite curious to try.

"Those who preach the myths of audio are ignorant of truth."