Armada ar6 - Durable, quick, sitff in the tail but soft in the tips for easy buttering, good on rails/jumps/all mtn, whatever.
Line Chronice - Pretty similar ski really. It's stiffer and cheaper than the ar6 which you'll appreciate coming off GS skis, cheaper, really durable, SUPER light and succccch a good all mountain ski. I charge groomers, park, rails, crud, slush, ice, BC (not a lot of pow where I ski) any everything else with my chronics. For a beginner park skier, I'd recommend mounting them at -3 or -4. That way you wont sacrifice any all mtn performance and you'll still have a great park ski.
Volkl Wall - Stiff, really well built park ski. It's symmetrical unlike the two skis above so will be better in the park but worse all mtn.
K2 revival - New ski for 2011. Looks like a shitload of fun and it's got a cool graphic which is a bonus. It's probably the most unconventional ski out of all of these with it's jib rocker. Might be a little too much to get used to with your racing background, but give it a go. Slightly wider in the waist than the above choices too, so will feel a little slower edge to edge on groomers.
See if you can demo some stuff so you can make up your own mind what you do/don't like. For an all round first twin tip I'd definitely recommend the chronic. You really cannot go wrong with it as a first twin tip, or as a park ski in general.
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