I have a 65 Pally that uses this when going solo.
Due to aa's and buffs I am able to crit as high as 600+ with ave hits in 260-320 range. With new GoD wep aff. it will proc for me as much as 3-5 times per mob at 180 per proc. Thats alot of mana and dps and time im not wasting healing myself, its a great 2hb.