I'm a HUGE fan of DME, but I think if I was in your position I'd take a town car, if the thought of spending all that extra money wasn't a problem.
Since you have only carry-ons, no matter which way you go you'll skip baggage claim, so so far that's a wash. With DME you'll wait in line at the DME counter (even if it's only for less than 5 minutes if it's crowded), then wait in line for the bus itself, and then perhaps wait for other resorts to be dropped off first. With a town car, your driver will meet you and you will go directly to the car and directly to WL.
So in your case, my best advice would be the town car option. DME was very fast for me (53 minutes from getting in DME line to being dropped off at CBR), but since you're not waiting at baggage claim and not making a grocery stop I can't see how DME could possibly be faster than taking a town car.
Just keep in mind that if you save, say, 30 minutes by taking the town car, and you're paying about $120 round trip, that extra 30 minutes saved is costing you the rate of $240 per hour. Is your time worth $240 per hour? Maybe it is ... it's your call! ENJOY YOUR TRIP!
-- Eric
