It turns out that speakers "A" were the Axioms and "B" the Energy pair. It also turns out that overall, I preferred the Axioms - which was somewhat a surprise. Here is where they did much better than expected:
1. Bass Extension
2. Sound Staging and Imaging
3. Lack of harshness
4. Microdynamics
5. Macrodynamics
Ok - They surprised me pretty much everywhere. Axiom's constant work on improving their designs through research at the NRC and double blind testing on products to ascertain if the "improvements" really are seems to be paying off.
I am not going to get into a "this vs. that" between speakers now. BUT, I have has the following high end speakers in this same room as the M80 V.2's:
PSB Strata Goldi's, Legacy Classics, VMPS Super Towers, Klipschorns, Onix Ref 3's, Infinity IRS Sigma's, and Paradigm Studio 100 V.3's.
These speakers all have an average retail of about $5500 per pair.
In "lesser" speakers, I have had Rocket ELT's, 550 Mark II's, Ascend 170's and 340's, Axiom M22's.
The "lesser" speakers are VERY good loudspeakers, but they cannot reproduce the macrodynamics of the larger, "high end" speakers.
The Axiom M80's DO fit in with the better tower speakers on the market.
They have solid 30 Hz bass, image like monitors, yet have a large, expansive soundstage. I never sensed a hint of harshness, nor brightness. In fact, I found them to be quite neutral, with the ability to get out of the way of music.
As played against the Energies, the 2.4i's matched the dynamics of the M80's, but did so with a somewhat "mellow" signature - think original PSB Strata Gold's, and you will get the picture. As Roly has suggested, the 2.4i's are not going to be the "value" speaker in the Energy line, and there are likely a couple of better choices for a direct comparison to the M80's.
Getting back to the M80's - They will excel in both a 2 channel or a home theater system.
One Caveat with these speakers: I am driving them with the $4500 Emotiva DMC-1/MPS-1 pre-amp/power amp combo and a highly modded Denon 2900 Universal player.
Make sure, if you are interested in these speakers, that you get amplification and front end worthy of them. I can easily understand why people could consider them "bright" when using a $700 receiver.
Finally - Soundstage recently did a review of the M80 V.2's and had done a review of the 2.4i's last year. Here are some NRC graphs of both speakers. Feel free to chime in, and questions are welcomed !
This is the response curve of the M80 V.2 - note the almost uniform response across the 200 to 10,000 Hz range. They are also +/- 3 dB from 60 to 19,000 Hz, and - 5 dB at 32 Hz. With typical room gain, they will be flat to 30 Hz.
Here are the 2.4i's. Rather than a +/- 3 dB curve, they are closer to a +0/-6 dB curve - which matches the somewhat mellower curve mentioned. In a perfect world, both the Axioms and the 2.4i's would b +0/-0 db - but staying within a 6 dB total window, especially with NRC style measurements, is remarkable.