Tim, when I tried to type "artificial sphincter" I misspelled "sphincter" and the spell-check helpfully suggested "spinster" as a correction.
Talk to your urologist about it. I am so freaking happy with mine. I never worry about waking up on the "moist side". I feel a slight bladder pressure early in the morning when I have to go, and that's it. During the daytime I push a secret button and deactivate it and turn it back on right before bed.
I think many doctors are (rightly) concentrating on getting us through our cancer, and (wrongly) not paying enough attention to our after-surgery lives. This is where we have to bug them a bit. Twenty years of wetting the bed didn't sound good to me, and definitely not to my wife, who makes the bed....
Some of us will just never regain 100% nighttime continence. That's just a fact of life, and no matter how many kegels we do, or how often we set the alarm during the night, instead of waking up dry and happy we're going to wake up...well... pissed.
Zach