Here's my 70lb monster today after his last hunt of the season. Very good dog in the field and a very good pet. We have about 120 lbs of gsp that sleeps in our bed under the covers. I've never had this adversely affect their ability to get the job done. They do need regular exercise or they become little ****s but that's just the nature of the breed. I would say that it is a very heavy decision/commitment but i am very happy with mine and will never own another breed.
-scott