I Like these headsets, if you on a budget these are perfect for the job, I own a set of these and also vic firths SIH 1 and EX29 isolation headsets, sound quality is good (note: they not produced for sound quality ie mixing or general listening to music, they are mainly for the musicians who are being recorded) I don't see much diference in quality between these and the vic firths, though I sense the vic firths maybe a tad tighter on the head giving maybe more isolation. Ill not go into EX29 as they are higher end and another story.
Anyway, when I got the T-bones along with a head amp I took them straight down to rehearsal room and did a session with the band, it was quite comical as all through the session we would be shouting at each other with the words "what?" and "what you say?" so I guess the only downfall of these as with all isolations, is a pain in the butt trying to have a conversation whilst wearing them...err more to the point...impossible...as for comfort, having eight ear rings in one ear, i never do find wearing headsets comfortable to a degree, there is nothing obvious about these and like the other headsets I have, you do tend to get a little sweaty after prolonged use of wearing.
Great headset at a great price, would definatley buy the T-bone HS990D again if more headsets were needed!