Sorry to post another thread about sizing help and sounding like a broken record! I have just ridden my first firewire alternator 6'0 whilst on a surftrip in costa rica and i am ON bOARD with the firewire revolution. I'm 5'11 (6ft on a good day) and 75kgs (165 pounds) and currently riding a 6'1 JS and a original 5'6 Peter Sheely Twin back home but i am looking into a double purchase to renew my quiver. I was looking at the 6'0 Alternator just cos the one i rode was perfect and handled my height and weight, as well as a pumping swell here that peaked at 8-10ft! My problem is I'm not sure on how small to go with the potatonator...? i was thinking anything under 5'6?? i would guess my level is low-mid advanced. I'm happy to go smaller of it will still handle my weight and fly?