Vic - tell me about the Mesa + Epi 4x10? I ordered a Titan yesterday but am still undecided about the cab - was able to try it with a Powerhouse 4x10, but there's no Epis about to make the same comparison.
(Rather than say, "and I play ____ rock" I'll say I play in a covers band that does REM, ZZ Top, Mellencamp, Poison, 3 Doors Down, old Beatles and whatever else you're willing to pay us to play...).
With the Series 1 and Series 2 being somewhat different... especially with the 10" speaker based cabs. The S1 is stronger through the mids, whereas the S2 is (at least IMHO) more even sounding, so the S2 is my favorite, tho it is not a night/day difference.
I like the Epifani 410's a LOT, but the Bergantino AE410 is also a very strong contender. The main diff is the Bergs will be tighter and more focused sounding, with a bit more going on in the mids, whereas the Epifanis will be bigger sounding... more going on in the highs and the lows.
To more specifically answer your question tho, with my S2 UL410, the sound is massive and loud. Clear at the high end, sometimes even to the point where I drop the treble control a bit. Full and rich at the low end, and also, sometimes I even cut the bass just a bit. The mids are also very present, but not nasal or boxy at all. Great mix cutting tone throughout and PLENTY of punchy headroom.
The bottom line is, either one would be a fantastic cab for the Carbine, but then again, IMHO, the Carbine is one of those heads that I think lots of cabs would be great with... including the Mesa cabs... I just don't get into the heavy cabs anymore. I go for the particularly lightweight NEO stuff, which is pretty much defined by Epifani and the new Berg AE stuff at the high end, and at the less expensive end, the Avatar NEO 410.