I never had a jpouch even though in the end I couldn't have one due to the mess in my rectum called cancer. I honestly didn't want one after reading about it so I went straight to the BCIR.
I would get a few opinions in your case though. Don't stick to one kpouch surgeon ;-)
The problems I have don't even compare to my friend's issues with the jpouch. I don't think any colon removal is flawless. I think everyone is different. I know a guy that has become a good friend, who posts his BCIR draining videos on youtube that hasn't had one issue, no pouchitis, after going to the BCIR from the jpouch. Then some have valve issues, some have pouchitis that can be manages with antibiotics.
I have other issues with my insides that makes it tough some days but I am different than others. I also had to wear a leg bag for 8 days when my valve spasmed and intubation was a pain and I will never take my pouch for granted, I don't want an external bag so I am sticking with this little guy for ever, no matter what
I still olympic weight lift, I go to my job 9 hours a day. I drain 3 times a day unless I eat something that gives me horrible gas then maybe 4.
I have no issues with absorbing foods/vitamins, losing too much weight, etc.
I eat pretty much anything as long as I cut it up good or chew it good.