Hm, its a few on the market.. and as always.. some will say that and some will say that.

deflex i do belive is the cheepest ones.. but not the best.. they also just come in to paper bags. (mine did=()

then u have powerflex, they are better and come in small boxes.

u also got superflex and some at rallydesigne.com that is better then that again. afther what i have heard

I use powerflex, but thou some deflex that powerflex could not get me when i order. and order the deflex to my cabby first befor i did get my s2