I was another who had a UC diagnosis later changed to Crohn's Colitis. I was then given only two choices . . ."trying" Remicade or surgery with permanent ileostomy.
I had strictures in my rectum which were stretched twice and each time led to more and more incontinence. My GI could not guarantee that Remicade would stop or even improve the incontinence. No fistulas, though.
One of the first questions they asked me when deciding if Remicade would even be an option for me was, "Have you ever had Multiple Myeloma?" Well no, but my dad died with MM at age 54--end of discussion.
However, I did do a little more research on Remicade and Humira just to make sure that I knew, that I knew, that I knew. Nothing I found even remotely wavered my decision. Short term results for many, potential for other serious complications, the expense, the infusions. I knew in my heart what my end result would be. Now or later . . . why wait, and be miserable with grandchildren to enjoy, and the simple pleasures of life passing me by. My colon rejected me, so I decided to reject my colon [I stole that comment from another, btw.]
I was counting the days until my surgery and have never once looked back. I made an informed decision which was the right one for me. Can't say it is right for everyone. Just do your homework and you do have the advantage of living with a temp loop ileo, so it will not be unknown territory. I have read that end ileos are easier to manage.
Good luck with your decision