Al Pacino - Is he really that good an actor?

I was just thinking about the new Robert Deniro / Al Pacino film Righteous Kill and wondering f I really want to see it.

Both actors have had amazing past performances but almost all in the same charater. I mean, we know what kind of roles they will be playing and we know the script would have been written for this. So will it just b like a Deniro, Pacino parody. A big joke, or can the two godfathers of gangsta acting really pull it off.

Heat was amazing but they shared only one scene. Godfather II again was great but they didn't share any scenes.

Are they really that good at acting, what have their recent attempts been like?