I don't think Dolan & Raymond are bad, but what kills me is when Dolan/Raymond (I can't remember which one it is) gets excited. He sounds like Kermit the Frog, and its the least inspiring call. He obviously cares, and is excited, but his voice takes on a nasally inflection that isn't what you are looking for in a good call.
Brownie is great for what he does, calls the plays and doesn't get in the way and lets JD tell the jokes, but when something exiciting happens (Biggio's 3000 hit comes to mind) it sounds right.
I just cringe at thinking about hearing some of the great calls of late (Jeff Kent's walkoff, Burke's walk-off) shouted in that nasally voice. The rest of their calls are fine, nothing spectacular, but they get the job done.
Speaking of Burke's call, I always laugh when I hear Ashby shout, "Chris Burke!!" Its as if he didn't know what else to say so he just shouts his name once Milo finishes his "Lining it to left...its gone...its gone...its gone."