Some guys are back to normal in a couple of months and others up to few years and a few never. There seems to be no shortage of doctors who want to work on this problem and there are a plethora of alternatives from pills to shots (way scarier to think about than to do) to implants and pumps and more. I had to use shots and then pills for a couple years.
Your urologist can talk to you about options but if he doesn't have a lot of experience doing the nerve sparing surgery get a new surgeon.
With a good surgeon you should be fine.
Of course you won't perform any better so we have to assume you do ok now.
By the way, you won't necessarily have to take Viagra long term.
Best of luck on the surgery,
Mike
