Elbows would scare me -- my vet told me the surgery techniques for elbows aren't as developed and reliable as hip techniques, and they're harder to treat successfully. I'd take a dog with hip issues over elbow issues, personally.
Have you talked with your own orthopedist about the prognosis based on the breeder's x-rays? If not, I'd pay for a consultation with a specialist (if there's a state university vet school near you, start there!). The idea is to make an appointment for an office visit, after first sending over the x-rays and breeder's reports. Let the specialist review them first, then meet with you. He or she might be willing to apply the cost of the consultation to your future surgery bill, if you choose to do it at that clinic. You'll likley spend under $100 and be able to ask:
- what's the worse case scenario, if the surgery doesn't go perfectly? (Multiple surgeries? Lame dog? Amputate? PTS?)
-what's the best case scenario in terms of the dog's future athletic ability? (No limits? Jumping? Running? Sporting events? Rough play?)
-what's the likelihood of the dog getting arthritis in the future, even if the surgery goes well? (it may be 7 or 8 years away, but you could end up with a dog with shortened quality of life--I'd want to know if that's likely to add that into the decision-making process)