Another fan of the G12-65s here. I've had V30 cabs (Mesa, Mills) and I like my old G12-65 loaded 1960B better. They are not quite as nasty and cutting as the V30s while still retaining that upper mid spike and they have a punchier low end than greenbacks while keeping that raunchy midrangy sound of them. Really fantastic speaker. I'd heard about them for years and lucked into a beat up 1960B loaded with them for $175. Having had them for a while now, I would have paid 3 or 4 times that and been happy.
They sound fantastic with my Mesa Mark III and my Mesa Electradyne has never sounded better. On the downside, they don't pair well with my Diezel Herbert, IMO.
If you can't find original G12-65s and don't want to pay for the reissues, Weber has a nice clone of them for about $50 less a pop.
I also have some ceramic Weber Blue Dogs that, though they sound completely different and aren't even close to the G12-65s, I would describe them nearly the same way. Bright, cutting, upper mids, big low end, nice girth through the midrange. The Blue Dogs break up a lot more though, even the 50W versions I have. Very nasty speaker and I mean that in a good way, but definitely more for a vintage sound than the stadium rock the G12-65s were made for. Probably not what you're looking for, but thought I'd mention it.
