Which Six Flags coasters are completely enclosed and include several pre-shows? If you count GotG Coaster as Six Flags-ish, then I invite you to go to a MK thread and complain there that Space Mountain is just a Six Flags ride.
Folks embarrass themselves by comparing any wdw attraction to Six Flags. It is hyperbolic to the point of automatically losing an argument.
I like my local six flags. It is a nice distraction. But at $70 a day....c'mon.