Demo Bindings???

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Demo bindings are usually less durable than non demo bindings, but if you're happy with a marker griffen I don't think you'll have problems with a higher end demo binding. A lot of normal bindings have a good adjustment range so depending on how much you think your feet will grow you might be fine with a non- demo binding. I think you'll be be fine ether way.

The joy of the Griffon/Jester demo binding is that unlike every other demo binding out there it doesn't have a heavy and thick metal plate to it.  They use a longer track for the toe and heel but are no thicker than the normal binding but allow for tons of travel front to back.  The longer track does affect the flex of the ski but only slightly and you keep the nice low stand height of the Griffon/Jester binding.
All said and done they cost more but if you are concerned about remounting and are picky about your mounting point they do address that problem without any significant impact on performance.

Agree on the binding, its the best of the demo's I've tried so far, but they still are not as solid as the regular binding. All the Marker toepieces always seem to eventually get a little loose, not very comforting...

thanks for the info. I can get my hands on a pair of Jester Demo bindings for a pair of JJ's. Do you know how exactly it would affect the flex of the ski? Thanks

It will feel stiffer under foot. Its like supportin a structure which is likely to bend with a solid bar over the area it is likely to bend it will limit the flex. By adding a fixed metal rail to a flexible ski you are limiting the amount the ski can bend as the rail will be stiff so as not to warp and make changing the binding position harder .

I'm running 2011 Demo Griffons on my Kung Fujas, and they work great. I was in the same boat as you last year, since i was scared that i would have to remount cause of my feet growing, but they work really well. Shredded 1 season powder & park on them and no problems. The other nice thing is you can move the toe and heel peace forward and backwards, so you can actually change where you stand on the ski by like 1.5cm, kind of like the schizo.