YES part owner DCP
Amine from RUSH Distribution who handle YES Snowboards in Australia just sent us thru this info we thought we'd share with you all...
I managed to get to Mt Buller on Saturday, for my first skid on the 2010 YES bards. We rode four of the sizes (149, 154, 156.5, 158), and three of my Victorian accounts demo'd them as well. Here is our feedback.
Overall - the flex of the boards is solid underfoot, and gentle in the tip and tail. All sizes were very comfortable to ride (I actually thought they would ride a lot stiffer than they did), and we put this down to the regular camber between the feet, and the reverse camber in the tip and tail. My final conclusion - the boards were solid at speed, yet easy and maneuverable at slower speeds (ie. jibbing). A good mix of REVERSE camber playfullness and REGULAR camber grunt.
149 - this board gave me the maneuverability of a 149, and the stability of a 152. It had a loose playful feel on slower runs / rails, yet held on very well at speed. Great board to down size someone on who wants to jib, but still get impressive all mountain performance.
154 - this board rode like a 154 (funny that). Just as easy as the 149, awesome DO EVERYTHING board.......broadly salable, hard to fault.
156.5 - holy shit..... this board was unbelievably comfortable to ride (everyone please remember how short and unfit I am). I thought I would struggle more, especially as it was my first day riding after a 2 year injury, but it was a breeze. I rode this size last, when the sun had disappeared and the runs had started to firm up, and it did not matter. The ULTIGRIP made everything feel like a fresh groomer, I was unaware when it became icy = it's grip was impressive. It was smooth when put on edge, it wasn't 'grabby' or didn't noticeably change speeds when going from one snow type to another. It even slid boxes well. I would like to see ULTIGRIP on all sizes next year!...I'm a big fan.
158 - I didn't ride this one, but some of the taller testers did. Very stable underfoot, torsionally stiffer in the tip and tail than other sizes. General consensus, a great board for faster, heavier and more FR orientated riders. 
YES hopes to see you at the following Demo's ;
June 27 & 28 Perisher
June 29 & 30 Thredbo
July 11 & 12 Buller
July 13 & 14 Buller
August 1 & 2 Falls Creek (tbc)
August 15 & 16 Buller (tbc)
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