I am another vote for the Mirena IUD being horrible. I had the mood swings, depression, etc. worse than I did on the pill, so bad that I went on anti-depressants for the first time ever. I started thinking about the timing and pulled the IUD and voila, felt much better. I pulled mine myself. I hadn't really planned to actually pull it out, but I was checking it after a period and decided to see if it would move and pop, it was out. I had another friend on it at the same time and she ended up getting her pulled for weight gain and headaches. Another friend's FELL out.
It also hurt like unmedicated childbirth going in. Not sure if my doctor wasn't so great at doing it, but it took her way too long and hurt like crazy. I had whacky periods and bled A LOT for the first 3 months and then they did go away for about 5-6 months, then back to heavy bleeding for a couple of weeks, then gone again.
Last negative - hubby could feel the strings and they were pokey.
ON THE OTHER HAND - I have a good friend who has had several and LOVES them.