I bought a cheapish 2H to mess around in A1. I tried it in A3 and it worked pretty well behind my monk friend tanking (ended up clearing A3). Went and got some upgrade pieces to boost DPS even more and went to A2i to try it out.. surprisingly effective! I cleared about half of A2 with 5 stack. The only mobs that gave me a bit of trouble was an elite swarm group with molten that kept flying around covering the entirety of the ground in lava.
(buffed w/ battle rage & WotB obviously)
In A3 I float around about 8500 armor and drop DPS to around 25-32k depending on whether or not I spec out battle rage.
The only problem is sometimes you run into stuff where you definitely NEED 9k armor, 1k resists, and block so I carry around Justice Lantern, my shield, 1H and SoE just in case shit gets real.
I'm probably going to keep this build and even if I go defensive, I'll probably swap to 2H/DPS gear when I pop WotB to do 4x the damage I usually do.
BTW.. not sure there is anything more satisfying than procing revenge in a group of trash mobs and just one shotting them all :lol
I dropped to 43k BC/90k WotB to gain back some HP/resis
This has a lot of good information too:
http://www.clicktoloot.com/p/combat.html
Lots of theory crafting/info finding here:
http://diablo.incgamers.com/forums/forumdisplay.php?167-Theorycrafting-and-Statistics