[AxLxExX]

I think it pretty much comes down to 110 AP vs. Berserking. I chose Berserking because I use a faster weapon as arms (made sense to me....)

Does anyone have any math that would back up the stronger decision? Constant 110 AP or a proc of 400?

[Muffin Man]

All the math I've seen puts Berserking ahead of Massacre in terms of average AP gain (you can find this on the wowhead comments for Berserking I believe).

BTW, Berserking uses a ppm system meaning it's proc rate is normalized depending on your weapon speed.