"Have you ever had sex with someone who has an IUD. Or talked to a woman with an IUD to see her opinion on it? Because it's not all you make it out to be."
Where does the OP say anything about a change of sensation in men?
Yes; I was conceding that I've never had sex with someone who has an IUD, only talked to them. You'd have to ask nekitamo what exactly one should learn from having sex with someone who has an IUD.
As someone who has sex on a regular basis with (one) woman who has an IUD, my experience has been that it has no impact whatsoever if installed properly. The uterus (where an IUD lives, naturally) is not typically involved in the act of sex.
Where does the OP say anything about a change of sensation in men?