Before you purchase any Sintra maybe go into some local hardware (and probably other stores) and see first if they're signage is made of it, then if they're willing to get rid of it. My wife works at lowes and brought me big 4'x4' sheets of 1/8" and 1/4"
everything looks great man but from what i saw of your main chest armor you might be stuck with the heat. thats the price for looking awesome. it would be nice if the had some conventions inOctober - April though! Hopefully it'll cool off before DragonCon
maybe a snap together button on the top center of the ab piece. mine does that and i'm probably going to use all snaps once i make a vest out of real leather.