I have the copper one. It's the best birth control I ever had. No hormones to mess with my mind, no prescriptions to refill or pills to remember to take-- and it lasts just about forever!

The only downside is that I now have a regular period and it's much heavier. I haven't had any problems with cramping. I think I might have had cramps the the first couple of months, but it's been 8 years since I had this put in, so my memory is foggy.