Blink dog is what i am using on my GWF to proc my bonding. I think its a really underused companion atm. Good active bonus - good gear slots + a fast attack rate and teleport for bonding procs. Plus its cheat. The only downside is that 1 defensive slot.
The Mercenary is better imo, but the problem is that he has a hard time proc'ing Protector's Camaraderie/Friendship (assumed a bug?)
The combat advantage bonus is good because Daring Shout gives you combat advantage on your marked targets, no matter where you are standing. Currently, two CA companions would multiply their benefits, giving you 25% combat advantage. That is being fixed/changed on the 18th. It's a good fast strike companion if you don't have the fire archon. It could end up in your final build...that or another companion that boosts damage.
Comments
To answer your question, it would depend on what companions you already have, and how badly you need the AD.
I think its a really underused companion atm. Good active bonus - good gear slots + a fast attack rate and teleport for bonding procs. Plus its cheat.
The only downside is that 1 defensive slot.
The Mercenary is better imo, but the problem is that he has a hard time proc'ing Protector's Camaraderie/Friendship (assumed a bug?)