Hi there, Bob-
Welcome to the site.
What is the reason for your needing this surgery, congenital, rheumatic fever, or something else. Not that I'm being nosy, but it might make a difference in how you view your new valve.
My husband has had 3 valve surgeries, and 2 lung surgeries which are as bad, if not worse than heart surgery. I can second what Ross has said about additional operations later in life. It is not only the obvious healing which can take the body up to a year to fully finish, but the body suffers a great deal from the additional trauma of major, major surgery. Even though the surgery will go just fine, that was true in my husband's case, your body still has major issues of many natures which go on and aren't there during the first virgin surgery.
My husband had rheumatic fever as a teenager, and the aftereffects of rheumatic fever can stay in your body for a lifetime. His first surgery was for an AVR, his second was for an MVR, and the third was to repair a leak in the mitral. In addition, he has a pacemaker, and his tricuspid is leaking, but does not need surgery. He's been on Coumadin 25 years, soon to be 26, and has had no bleeding issues associated with Coumadin in all those years. He was very active as a younger man. At this point in his life (he's 72) he would be very, very high-risk surgery, if anyone would agree to do surgery on him. His body is now hyper-reactive to anything that comes his way.
So what I am getting at is that various medical conditions can have very different scenarios. With something like rheumatic fever which is ongoing and can be progressive, you might want to consider a mechanical. In that case it would be very prudent to avoid as much trauma to your body as possible.
This is the most difficult decision, as you have no doubt seen from all the debates about it.
Best wishes.