My weight runs from the low 150's in the summer (skateboarding, softball, riding bike everywhere) to 160 in the the winter. I ride a 151 Graft, which maxes out at 165lbs. It's really flexible. If I was pushing the weight limit more, I'get worried that it would lose some of it's "all-mountain" ability. Go with the 155. You'll get more out of it over-all.
And be warned...the Graft is one of the funnest snowboards ever made, IMHO.
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