It is very difficult to find gutpunch-receivers and gutpunch-givers ready to play who can be trusted to stay within reasonable limits. The problem is that if over-done, this can cause serious damage. If done with finesse, it can be intensely erotic to those who are really "into it." I met a guy who was really into giving punches - it got him off tremendously - but he was looking for somebody who could take more than I could receive at the time, since I had fantasized a lot but was really new to that scene. So we never had a repeat.
One of my most intense experiences as a receiver was at a sex-club on the lower East Side of Manhattan (way out east on Houston Street) that was hosting the NY Bondage Club for a while. One of the regulars put me through a scene that was really shattering. He knew what he was doing. By the time I called a halt, I was actually too light-headed to stand up, as the mild battering of my abs had drawn so much blood to my torso away from my head! (I was tied standing spread-eagle, open and exposed to receiving.) Intense! But, of course, this has to be done with close attention to how the receiver is doing - checking in frequently by the giver - to avoid causing real damage. On this occasion, he was closely observing my reactions and knew when to slow down, when to massage my abs, when to stop, untie my wrists, and help me to sit down, bringing water for me to sip.