the k pouch was the predecessor to the j, with the j considered an improvement/advanced resolution . i started with the j, in 1999, but it failed due to pouchitis that was not responsive to treatment, despite many types and woefully too long term. like others with js, which failed for one reason or another, i faced a permanent ileostomy. most gi surgeons only suggest the external bag as so few are familiar and capable of creating the k. for example, here in boston ma--a known medical center--there are no docs who even suggested it let alone would do the surgery! i became informed through this website (thank you my k korner family) and had the surgery at cleveland clinic in 2015.
i'm don't recall the j's failure rate, perhaps 10%? please can others reading this chime in? don't want to frighten you!! bric and ks also have a failure rate. as i understand there are new drugs for uc. are they not working?
finally, to answer your question!! the times when the j was healthy were better than the k. but also, one must face reality. in hindsight, my quality of life is fine, just different, from when i had a colon and functioned normally.
stay strong and healthy. jan