Which is pretty much nil, since Exp + Mastery gear doesn't exist at the current tier.
Justice points panties + belt and for raid drops there are gauntles from Chimaeron and boots from ZG. And there are a lot of exp/x items you shouldn't totally ignore if you're wearing gear with (way) lower itemlevel, agility + more armor is still king.
Just look at the epic pvp shoulders (+ hands for another 70 agility set bonus), providing only exp (and +crit) but a lot of agility, base armor and also an agility socket bonus. You did wear pvp gear during long terms of Burning Crusade and you can wear it again nowadays without being ashamed (even after reducing the set bonus drastically) until you can get your hands on loot with a neat secondary stat.
Or while gearing up you'll most likely run ZG/ZA a few dozen times and grab a lot of exp/haste and exp/crit items until you can replace them with better itemized raiding gear.
Edit: just created two sets, one wearing full pvp gear + boe haste/mastery pole and the other wearing full 353 gear + the very same weapon, both got Tia's Grace and Fluid Death for trinkets and full raid buffs.
It's really not that bad, slighty more avoidance, hitpoints, bigger SD-shields (thanks to additional attackpower) and migitation via armor but way less SD proccs in general (363: 85.6% chance to not connect versus 76% in 365 pvp gear).