For the most part, for my sons, their favorite part (and their roommates') of them being ICs was that on travel/tournament weekends, they did not have to "participate" in SAMIs.
There are a lot of cons, there too: they arranged to take GRs (exams) BEFORE they traveled, which was difficult sometimes. Labs could be especially tough to work around. They must be EXTREMELY EFFICIENT at studying, day planning, etc.
On the other hand, they got to go to California and the coach rented jet skis and everyone had a great time in the surf, several times.
So, there are pros certainly, and definitely cons, most of which were mentioned here. For some kids, it might be hard for them to consider themselves as "NOT a tennis player" or NOT a fencer, or not a xxxx. It might even be difficult for the cadet's
parents to accept that their child is no longer participating in a sport that mom has driven him and his sack-dinner to, to the tune of 20,000 miles a year over four or more years. Dad may wonder why Junior doesn't want the thrill of the gridiron, or the buck-up-and-take-the-pain of boxing or water polo. And, some cadets might not want to disappoint younger siblings or older coaches when they just would rather be in the Dungeons and Dragons club, or the BlueBards, or intramural frisbee golf.