We did bilateral TPOs on our GSD Leo. In retrospect I see both pros and cons. I'm not sure we made the right choice but I'm not sure we didn't. How's that for no help?
There's a TPO yahoo group with a lot of very helpful people but (not surprisingly) most of them are pretty pro-TPO. There's also a hip dysplasia yahoo group that has more of a diversity of approaches. I joined both when we were going through this and recommend them.
In our experience:
Cons - Took a long time to heal which meant much of his young adulthood was spent in a crate. He now walks with a slightly strange gait (although I'm told I'm the only one that notices). Since it's preventative, it's hard to tell whether or not it has helped. Expensive.
Pros - No complications and relatively straightforward recovery. He is 3 now and runs, jumps, and can go on long hikes without apparent difficulty.
Though only time will tell whether we've successfully avoided the much more risky THRs down the road.
If you end up doing both hips, I'd recommend doing them one at a time even though that doubles your recovery time. I know it sucks but I'm told that the chances of accidental fractures and complications are MUCH higher when they literally don't have a good back leg to stand on.
Hopefully others will chime in here and feel free to ask me any questions.
