Hey, 07KRO.
I had the surgeries a few months after I finished university - actually had the colectomy on my birthday. Takedown was a month later. In-patient recovery was about a week, but I was in the emergency room just a day later.
Complications from ileus kept me in the hospital for another month. Basically, my intestine forgot how to work and wasn't moving anything through. I'm not sure how common the problem is, just that there's a chance with major GI surgery.
Three weeks after that finished, I was back in the emergency room, fever of 107.6F. The infectious disease specialist said my intestine had a very small breach somewhere. The breach healed itself almost instantly, but some of my gut contents spilled into the rest of my body. Blood poisoning. The doctor wanted me to stay for a week, but I complained a lot and was a bit of an irritable ass from opiate withdrawal. They figured a way for me to leave after 48 hours, if I came back daily for some IV meds.
So, just that whole span of time was about 3 months. The whole time I needed increasingly more potent painkillers since my tolerance was going up. By the end, I couldn't even feel a difference after popping three dilauded/hydromorphone. Withdrawal took nearly two weeks of getting fevers, then freezing, muscle spasms, generally hating life (dysphoria), and being not-so-nice to everyone.
Either today or tomorrow is my 4-year Japanniversary. So, I needed about 2 years until I was near-ready.
The medical situation will, of course, depend on where you go. A big issue for me has been getting decent English support. It's quite easy in Tokyo, but pretty difficult in Osaka.
The gastros can handle my case. Quality of treatment is generally high, but also very different at times for legal or cultural differences. (For example, even immediately after surgery they will not prescribe anything stronger than ibuprofen.)
Gotta read up a lot before moving anywhere.