I have used it in C-Sections. We typically pull the epidural after the section anyways. The company data shows better and longer pain relief compared to morphine. The patients all stay for 48 hours anyways. Too bad I don't know the cost of this drug, but I'm guessing it's significantly more than preservative free morphine. No real bad side effects compared to morphine in my limited experience (about 30 cases).
I have also used it in radical retropubic prostates and had a bad case of respiratory depression that lasted way too long. Narcan drip, tied up an ICU bed. Probably not the best drug in the elderly, but for younger patients not so bad.