My cat had it done, he had many many instances of blockage, and this was a last-ditch effort to save his life - and it worked. It was major surgery though, and took quite a while for him to recover, and he had to use a special litter, and have one of those plastic cones that stopped him from chewing at his incision, for I think maybe two weeks or so afterward. Plus he stayed on the low-magnesium special diet food to help limit the build up of crystals. It was pretty expensive, but worth it for me, he would have died without it. He never had a recurrence of blockage after the surgery.
Sadly, my cat passed away about a year later though, of an unrelated cancer, so I can't say what the long-term results might have been.