Hey there,
is you want cheap kite for strong winds (20-30ish knots) get a Pansh. I got meself Pansh Blaze 5m, its no blade but in strong winds it is the best $120 bucks I ever spent. Check out their web site: panshkite.com.
P.S. if you do deside to go this way I sugest you get some decent lines (from flexifoil).
P.P.S. the Blaze does give you plenty of lift in those kind of winds but apperently you can get Pansh Ace which is chinese version of Blade for fraction of the price.