This is only my second cruise I'll be taking in two weeks, but I plan to pre-pay my tipping in advance this time. I like the fact of just getting it out of the way and not over analyzing the service all thru the trip or how much money it will end up costing me in the end. I also think these employees depend greatly on these tips. The service would have to be awfully bad for me not to pay it or less than the standard. I'm considering pre-pay because I've cruised with RCCL before and the service was exceptional. I'd never do it again if I pre-pay and the service was bad, but I've only heard nothing but positive things about pre-pay tipping. As far as paying additional money at the end of your cruise, if the service was exceptional, throw in a few more dollars for each of your servers, after all they probably deserved it and it would make yourself feel better.