I am atm using Cava's profile with my Level 85 Shadow Priest (With all heirloms except pants + Guild EXP Bonus) and after nearly 1Hour he made 2,9Million Exp. Is that good or should i replace the level 80 heirloms with some lvl 85 eq?
Why are you still using heirlooms? Past 85 they are all useless. Their stats are terrible too. Common sense.
Level 80 heirlooms stop giving XP bonus after level 80 so you are better off replacing them with Cata greens with much better stats, as the heirlooms won't scale up. Heirlooms have their level requirements written on them, for example Herlooms which say "Requires levels 1-80" will only give a bonus and scale up their stats up to level 80. Heirlooms which are marked as "Levels 1-85" will stop scaling and giving a bonus after level 85, so read their descriptions and don't use lower level heirlooms as you will get poor stats and no extra exp benefit.