Hi F.!
I have had the paragard since October. I am thrilled with it. I had a baby in Sept and had this inserted at my 6 week check up. It was easily inserted and didn't hurt at all. I wanted a birth control that was reliable . . .this is it. I don't even have to think about it (well, just to check on the placement once a month). My husband and I are not sure if we want more children (we have 2 children), and this seemed to be the best and safest for us!
I have had no problems with it. The reason I chose this one and no the mirena was simply because I am a mad woman when I get hormones. I wanted something without hormones.
I did reseach on both of them and got great responses. I have friends who have had theirs taken out (they wanted more children) and I am told that its a simple procedure to take it out (easier than getting it put in, actually!).
Good luck with your decision!
B.