Having owned several Lib/Gnu boards with MTX, like a T. Rice, a couple TRS's, and several Rider's Choices, they are definitely the real deal. However, if I were to get a Mervin board now, the only ones I'd be interested in for the riding you're describing, are the T.Rice b/c of their C2BTX and the Jamie Lynn BTX b/c its magnetraction is much more mellow.
16 Gnu Swallow Tail Carver . 16 NS West . 15 NS Snowtrooper BIA
16 Burton Genesis X . 15 Now Drive
16 Flow Talon . 14 Flow Hylite