Optics have already been covered, so wanted to comment on handling. Bought into the 6008 system back in 2008, and think it is ergonomically one of the best MF SLRs to have. It is heavy indeed, and I wouldn't walk around all day with it around your neck, but in your hands it handles well when used with the grip. Because of its automatic exposure meter, it is very quick to expose, compose and shoot. And for those important shots, the mirror lockup and self-timer buttons are at your fingertips. I think the price for the basic body/80mm lens has actually gone down in price since 2008, so they are relatively cheap now, compared to yesteryear. However, the other lens in the lineup, and accessories, have gone up in price (in pace with other brands), so it may take a while to build up your lens lineup. You should determine if you need wide-angle, macro, or telephoto lenses to see whether they fit within your price range.
A comment on the film back loading: my friend bought a Hasselblad 500cm at about the same time, and when comparing his loading of a Hasselblad back to my Rollei 6008 back, there is no comparison -- the Rollei is a snap, the Hasselblad is fiddly (you can see many fiddly examples in Youtube).