I used them in my last place, simply because they maximize interroom isolation and most of my recording (at the time) was pretty loud rock'n'roll. And, in that context, they weren't a big problem, at least while tracking a band, or loud guitars, etc. However, they were too obvious while tracking vocals, and presented a bit of a hassle. Fortunately, the studio was extremely well insulated, so it was possible to get the room to a comfortable temperature before a vocal session and get away with no HVAC function for as much as two hours. It also made for a nice excuse for a break.
Not the answer you're looking for, I realize, but Fran already covered that.