stats to start heroics at 80?Follow

I just dinged 80 and was wondering what the minimum stats are for starting heroics (sta/armor/def/hit rating)? I have about 525 defense (when my shield is equipped) before buying the rare gems, 20k health and 20k armor. Most of my gear is the tempered saronite, plus the titansteel shield. I figure that I can get to 540 defense without too much trouble.

I'm also slowly crafting the titansteel pieces. Should I continue along those lines? I was thinking either the mace or the boots next.

I'll link to my armory entry, but at the moment I have two fist weapons equipped (trying to get to 400 unarmed, stuck at 399).

Thanks

http://www.wowarmory.com/character-sheet.xml?r=Undermine&n=Spackledwarf