The majority of people who have J-pouch surgery are glad they had it, and most of them aren't having significant issues (or describing them in these forums in scary detail). On the other hand, the folks who have the surgery have chosen it over a permanent ileostomy, so their overall satisfaction is probably partly due to a good surgical outcome, and partly due to having a more natural external appearance and body image.
J-pouch surgery is more complex than a permanent ileostomy, and the recovery is more challenging. As Marie points out, you don't "have to" have it. Both paths tend to lead to reasonably normal, healthy lives (the exceptions to that are easy to find here). With a well-functioning J-pouch you can expect 4-6 poops daily, softer than with a colon. Some folks adjust their frequency or stool consistency with things like Metamucil and Imodium.
I chose a J-pouch because I strongly preferred to avoid an ileostomy, if possible. It turned out that I got healthy enough to take up some activities that would have been rather complicated with an ileostomy: scuba diving and martial arts.
Whatever you choose, I hope it goes very well.