Personally, I like to check out in person, IF I have time and IF I can't view my bill on the TV (you can at most Hiltons). Why? If there are inaccuracies on the bill, I'd much rather deal with them then and there, versus having to hassle with disputing a credit card charge farther down the road. Also, if it's somewhere I stay frequently, it gives me more "face time" with the clerks and increases the chances they will remember me (hopefully favorably) the next time I check IN.