I had the Mirena for 1 year and 8 months before I took it out. It was good, short light periods. But the last 2 months I would get pains that's why I took it out, Thinking it was the mirena, but I still had the pains after so I guess it was just my body.
I want one for sure after I have my baby. Every female nurse and female doctor in my ob's office has one and they say that it was the best decision they ever made as far as bc because most others mess with your hormones, and make you gain weight and whatnot, and the IUD you don't even have to think about. Do your research though and talk to your doctor to see what option best suits you.
I've heard bad things about long term birth control so it's not something I'd use but that's my personal opinion