I am using Johnson & Johnson Acuvue 2, which is (roughly) weekly disposable, and I continuously wear them (i.e. I don't take them out at night). I haven't had a single problem with them, and they're very comfortable. Much better than the old Acuvue, which used to get dry and sticky at times (at which time I used the special lubricating drops). I find that Acuvue 2 don't dry out even on long-haul flights.