Haven't ridden either, but the Nitro Magnum and K2 Slayblade wide are both amazing boards from everything I've read. I would def recommend the NS Heritage-XR 166 which has rocker camber, variogirp, super long effective edge, and a 26.9 waist.
18 Snoplanks Asym Fish . 18 Arbor Terrapin . 17 NS Maverix . 17 NS Twenty Five . 16 NS Swift - 14 TJ Brand Retro Fish
18 Rome Katana . 17 Burton Malavita Wing . 16 Burton Genesis X
16 Flow Talon