Gedman,
Since I had an AUS installed in the same area that the implant goes, my wife ordered me something called a "Nutty Buddy"! It is like a athletic supporter made of hard plastic. See the videos on youtube.
A guy has a baseball thrown at his "Wille and PoBoys" with no damage done. I don't know if that would help you to protect against "premature lift off" but I will be trying my "Nutty Buddy" out when I begin riding a bicycle soon. I have my AUS activated this Thursday morning.
Good luck with your decision. Sounds like a plan, the possible SE of trimix scares me too much to try it. Having been incontinent for 22 months makes me not want to switch one SE for another.
Bill from Florida