i've never played either course but i know people who play shadow creek all the time and never play at the wynn even though wynn is insanely convenient if you're on or near the strip.
both courses are probably close to the worst value for a round of golf that you'll find anywhere. you can play pebble freakin' beach for $500!
if you're wealthy, why not, but if this is any kind of a splurge i'd probably advise you to play a more sanely priced course or try to finagle a round at TPC summerlin or something.