I guess it depends on what you deem as overpay. To me, if you can get a special player who can change the game at a position of need and a position of importance, then I don't know that I was say you are over paying. He's worth the money.
Namdi is not Suh, IMO. Namdi was a bad idea from the start and most everybody new that. I don't think people look at Suh in the same light. Namdi was going to bring a championship to Dallas. Suh might be a guy who could do that. He is a guy that, if added to this defense, could potentially make it dominant.