I seem to be in the minority here. I have a horizontal router table and raise my panels using my biggest router. I have used a 1-1/2 HP PC router in this setup and since I'm able to keep the RPM's up with the smaller diameter cutter, it whizzes through nearly as fast as the 3+ HP model. As far as the backside cut, I'm firmly in the plane to 5/8" camp unless I get a panel that's too big for my planer. Then I just chuck up a straight cutter and have after it.
Jim