Never been to Winter Park. It's certainly getting trashed in this thread.
Much depends on one's preference.
I have 30+ days at WP/MJ and 20+ at Copper.
Copper - more commercialized.
WP/MJ - more laid back. Especially MJ side.
Trees and groomers - better at Copper.
Bumps - Hands down MJ. Some of the best zipperline bumps in NA. Copper bumps - a big MEH.
Snow - feels much better at MJ.
Disclaimer: When at WP/MJ, we usually hang out at the MJ side.