My recommendation? Get the M2Es if you have or are getting a sub, get the M3 if you're not.
Leaf, I don't think you can tell much about how a speaker will sound from its graph. I've had both M3Tis and M22s. I personally prefer the M3s. If you find the reviews for the M3Tis you'll see they are extremely well thought of - they are giant killers - extremely musical, rich mids, air, open highs - superb speakers. For what it's worth, if I were in your position, and my speaker budget was a bit tight, I'd jump on the M3s and never look back.
Here's the Sound Stage 2000 review of the M3Tis resulting in the M3Tis winning the best speaker award.
http://www.soundstage.com/revequip/axiom_millennia3ti.htm
Here's how Doug Schneider summed it up, "The M3Ti is a great inexpensive loudspeaker that brings high-quality sound down to a ridiculously low price. It’s not the only speaker of its type -- Paradigm and PSB have some models that do the trick too. But line this one up alongside because it is wholly competitive. When you listen to this speaker, you will hear a surprisingly refined product that may trick you into thinking it is more expensive than it is -- waaaay more expensive.
To me, this speaker is a true find. Try it, buy it, and if you’re embarrassed to tell someone how much it cost, spill the beans anyway. You'll look like an audio genius."
Of course, the M22s won the award the next year. Here's a quote from their comparison of the M22 with the M3: "Moving up into and through the midrange, the M22Ti SE continues to ascend to a level of liquidity that the M3Ti SE can’t quite match. I have to be careful not to step on the toes of the M3Ti SE; it’s a wonderful speaker in this regard. But the M22Ti SE has a more smoothly flowing nature about it in the midrange. By comparison, and only direct comparison, the M3Ti SE can sound a tiny bit grainy. The M22Ti SE does not, as should be the case for 40% more money. I also believe that the M22Ti SE's midrange performs a more successful segue into the treble, resulting in a slightly more seamless and coherent presentation.
To be sure, we are talking about a relatively small degree of improvement here, but a musically significant one all the same."
Colin Flood reviewed the M3s for Enjoy the Music. Here's an excerpt: "The low-priced Axiom M3Tis impressed me greatly with their clarity and resolution, particularly in the crucial midrange area. The midrange is open and clear. They have a level of smoothness normally associated with high-end loudspeakers. The bass and the smooth mid-range make for one very listenable and enjoyable charmer of a cherry box.
In fact, the only loudspeaker I have heard with a smoother, more liquid mid-range and crisp treble presentation was the JM Lab Cobalts, backed by Audio Refinement equipment. Yet, that set-up was four times the price. It was not merely smooth however; it bordered on the lush, Hagen-Daz™ rich and creamy side."
Although Doug Schneider loved the M3TiEs, he went ape over the M2s! Here'a an excerpt:
"As for the other stuff I'd been listening to, Ani DiFranco's Like I Said (Songs 1990-91) [Righteous Babe Records RBR005-D] is recorded rather poorly and is rather lightweight-sounding with too much high-frequency hash -- obviously, a subwoofer's not going to change that -- but now there was bass energy that helped balance things out. The already robust The Ghost of Tom Joad gained some additional weight, and that resulted in an even more majestic sound with an increased sense of space. Norah Jones’ piano on Come Away with Me [Blue Note Records 32088] had the sort of richness and vibrancy that I knew was there but was absent when the M2i was on its own. The bass guitar and drums were fleshed out so wonderfully and with such detail and control that I could do nothing but sit back and enjoy this speaker system -- a $255 satellite and a $3000 sub!
This Axiom/Revel marriage sounded similar to the excellent $5500 Ethera Vitae loudspeakers that I recently reviewed. The Ethera is still a bit more refined and articulate in the upper end. And it also has a little more see-through transparency -- obviously there is room for improvement in drivers and cabinets beyond what this little Axiom costs. But both systems share a clean, clear, open, uncolored, and "boxless" sound. These put into perspective just how much the M2i achieves. It’s an inexpensive, micro-sized super-achiever.
Family feud
The M3Ti SE, with its 6 1/2" woofer, goes deeper, and as a result is a little weightier-sounding than the M2i. Because of that, it’s actually closer to being the perfect all-around, low-priced bookshelf-sized speaker because it stands alone easier. Its caveat is that it’s not as neutral as the M2i. The mids of the M3Ti SE are a bit more relaxed, and that means that voices don’t jump out at you quite as much. The overall presentation from the M3Ti SEs tends to be a little on the warmer side, while the M2i is a little leaner. That’s precisely why Axiom says that the M2i has more in common with the $400 M22Ti SE than with the M3Ti SE.
Both the M2i and M3Ti SE play to about the same volume level, but when the M3Ti SE starts getting taxed, the woofer loses control and some port chuffing can be heard. It tries to do more down low, and its failure is more obvious. The way the M2i handles deep bass is by simply not doing it. Still, it gets stressed when played too loud, which manifests itself as some hardness and congestion in the upper bass and lower mids. In the end, each speaker can only play so loud, which is reasonably loud in even moderate-sized rooms, but the effects of the speakers hitting their limits are a little different.
Which speaker you should choose will depend on various factors. As I mentioned, the M3Ti SE and M22Ti SE are rather full-sounding speakers. If you are not a bass freak, you can easily get away with no subwoofer with either of these speakers. The M2i, though, is light down low and falls into the just acceptable range of bass performance. That makes for the next biggest difference.
When I played the robust-sounding The Ghost of Tom Joad I was surprised at just how rich and vibrant the M2is sounded. However, when I played something a little less forward and full, they sounded a bit thin. A good example of this is Ani DiFranco's Like I Said (Songs 1990-91), due to its inherently lightweight sound and excessive high frequencies.
All the Axiom bookshelf speakers can benefit from subwoofer reinforcement; it’s the M2i that begs to be mated with one -- and not just because it has the least extension. The way it rolls off in the bass seems to make it the easiest to match to a sub, and this highlights its prime advantage over the other two Axiom speakers if you choose to go that route."
