the other thing to keep in mind is grip weight can many times act as a counterbalance for swing weight
I don't know the headweight of the Alpha RX putter I won in the Monthly Giveaway here at GD almost 1 1/2 years ago, but it's been in the bag since. It IS a heavy head, and he shafted it with a double-bend shaft at 35"+. I used 14 wraps to build up the grip, and slipped the Winn Medalist over it. There's a whole lot of backweight under my hands, so it's got a real nice balance to it - can't see it going anywhere in the near (or far) future, it's that smooth.