I've become a fan of 12's in the past year - Not that 10's don't sound very good - but, as you've read, 12's do give a bit more muscular bottom end, while retaining most of the articulation you get from a 10.
I'm currently playing a single 12 cab from Dr. Bass. It's a hybrid of sorts, though - it's got a nice 6 and a tweeter. I love the sound (currently covering deep bottom with a Bag End ELF 18). I'm awaiting delivery on a Dr Bass 212 with the same 6 and tweeter config, but with punchier Eminence speakers (a Delta LF and a Delta). Once I receive that, Dr Bass is trading me the 1260 cab for a 115 (with a Delta LF). I'll let you know how the 212 sounds once I receive it. BTW, the 212 is rated at 900 w @ 4 ohms. I'm using a PLX 2402 with an F1X and SF2.
Mikey (Pookeymp?) from the Club bought a 212 from Dr Bass and was very impressed with it. He said the 12's project more bottom away from the stage than his Acmes did (I found the same comparing my 112 to my LowB2 Acme). Dr Bass is great to work with, builds light cabs (212 is under 50lb) that are indestructible and sound great. Marc, the owner, will help put together whichever combination speakers you want for the sound you are looking for. He's very flexible about continuing to swap speaks after he gets paid, too!
Anyway, that's my 2 cents. Have a great holiday, all!
Bill