So far, I guess I'm alone in that I no longer spar with any of the underbelts and only the black belts who are training to fight in competition. I have guys who kickbox and a few who want to fight NHB. I do roll with some of the bigger underbelts who want to compete in submission grappling.
I used to spar with most of the underbelts with the idea that I should have the best control and would be the safest for them. After one adult student tried to throw a punch at me and I went to check it, he hit my check with his face. It was kind of an interesting face plant actually. Since then, my wife has pretty much banned me from sparring (we co-own and operate the school...and it's obvious who the REAL boss is). She's worried about not only liability, but the perception of the students and families. As unrealistic as it truly is, some of the students and families seem to think that I should be perfect in my control and any mistake would HAVE to be malicious (or at least that is how my wife fears it would be percieved).
I'm not the only one, either. My chief assistant on staff (4th dan-who just happens to be her training partner and they beat on each other quite regularly) is a former ranked competitor and used to fight full contact quite a bit. One of the (then) 18 year old first dans liked to charge in a lot and ran right into a heel with his nose. After his Dad went ballistic about how his son's nose was broken (BTW, the father saw the sparring session in question and even agreed that his kid ran right into it and that Allen had pulled it, otherwise the injury would have been far worse, but still felt that his control should have been perfect and complete), my wife banned him from sparring ANY of the students for quite a while and still restricts who he gets to play with.