My fiance has a standard copper IUD and it's pretty much OK. She does get cramps of the first day or two of her period, but she did before so that's not necessarily relevant. She thinks they might have got slightly worse but not completely sure. Having her cervix dilated was painful, although it lasts for up to 10 years.

Before the IUD she was on hormonal birth control (I'm sorry, but I temorarily forget which one) which had the advantage of very light or absent periods but when they did come they were in the form of long and unpredictable spotting, now they're regular and over in about 3 days although much heavier than before although it took months to settle down after coming off the pill.

As regards getting poked: there is a tiny piece of plastic 'string' that just pokes through the cervix and which you have to feel for every few months to make sure it hasn't got dislodged. I can sometimes feel it during sex although it is rarely unpleasnt and only if I'm going deep enough to be at least a little uncomfortable for her so I don't find it much of an issue.

One thing to bear in mind is that you can't use a menstrual cup if you have an IUD, which is a minor nuisance because they're cheap, reduce incidence of thrush compared to tampons, don't have to be changed as often and are environmentally friendly. Apparently the 'string' is a potential route for infection so it's best not to leave menses sitting around the cervix longer than necessary.

On the whole she likes it as it is 'fit and forget', extremely reliable and doesn't seem to cause many side effects compared to hormones.