I'm going to be getting X1, I've been on 8.3 for some time, but my DAW died, and they're trying to revive it... Regardless, it's only a matter of time before the old quad core/XP/32 bit which has done very well, gives up the ghost. When/if they get it back, I'm going to get a new Win7/X1 mashing and begin the migration.
And yes, Fab's interface takes a little getting used to? But it's good stuff :-) I can't get my TS to work well with my current 8.3 Pro, but it may be a different story w/X1.