I played a 1975 Ripper for eight years as my main bass and gave it up only because I bought a Steinberger L2. Despite what others have said in this thread, the Ripper CAN sound like a P bass -- in fact, that's why I bought it after my old Precision became unplayable. The Ripper still is the only Gibson bass I like the sound of, and that's because it sounds more like a Fender. I never liked the EB Series basses or the T-bird, and I flat out hated the Les Paul bass. The Ripper can punch like a Fender but also can give you the low end of the EB series basses, but with less mud.
The neck on the Ripper is close enough to a P that I had no trouble making the switch, and -- again, despite what others have said -- standard long scale Rotosound 66 Swing Bass fit through the back of the body with no problem -- silk cleared the nut easily. Used them exclusively on this bass. The original Ripper has a four-position rotary switch that will give you a variety of sounds: #1 (both PUPS in series, in phase) is the fattest of the bunch; #2 (bridge PUP only) has less bottom but great punch; #3 (both, parallel, in phase) has a midrange, scooped character; #4 (both in series, out of phase) is so thin that I never used it. I briefly wired my Ripper with two coil tap switches and a standard three-way toggle and immediately hated that setup -- it never gave me the sounds that I got from the rotary, so I switched back. I still have recordings made with that bass and it sounded great.
I also never had a problem with the neck and found the oversized body not at all heavy or hard to get used to. Played both finger- and pick-style with ease.
All this said, $1000 is too much for a used Ripper. I wouldn't spend more than $700, and then only if it was in primo condition.