I had mine for a little over two years. I liked it, and would possibly get it again (though I might try the copper IUD instead--just to see if there's much of a difference). I had some heavy bleeding the first three months or so, off an on. I hear it's pretty typical, and I know lots of women who had it removed because they couldn't handle it. But after that, I was pretty satisfied. I had extra discharge, which made me more prone to yeast infections, and sometimes the string would shift so it'd be tougher to locate. But those were really the only two things that bothered me about it.
I've had mine since May. I like it a lot! Insertion didn't hurt at all (I was 6 wks pp). I have never had problems feeling the strings during sex or any other time. I still get my period, but I'm hoping it will just stop eventually. I haven't gotten any negative side effects so I'm pretty happy with it.