You're doing the right thing by being proactive about your health and surgery. Determining the best valve for you has a lot to do with the specifics of your case. A mechanical valve has longer durability, particularly in a young person, but has the downside of requiring anti-coagulation with Coumadin. A bioprosthesis doesn't require Coumadin anti-coagulation, but is considerably less durable. For complex surgery like yours, I would want to see a surgeon who does a high volume of cases. You would be best served with someone at a national center of excellence with high surgical volumes, even if it means travelling far from home for the operation.