The new X12 is pretty sweet, but to me I wouldn't pay a premium for it over the X11 which was already decidedly awesome.
A friend of mine has the italian-colored X11, and its really sweet. If you can find a closeout type deal on one of those, thats what I'd jump on.
I like Arai too, but Shoei is my brand. Fitment is personal preference i know, but I'm not a huge fan of the visor systems on the Arai. If you're already invested in visors for one brand or another, that weighs into the decision too.
If i was buying a helmet today, it'd be the italian x11. If i could get it for a deal? Even sweeter!