i have a radtec, due to them being more within my budget at the time, and i have no complaints, nice quality and fit, and appeared to do its job fine
always hear good things about grs for the more powerful cars out there, and i really like the look of the pro alloy units with the wind deflector plates
my mate just bought an airtec unit, and i must say i hope it functions better than it looks, because the welds look messy, and even the brackets seem flimsy, brackets would be better welded on like all the others rather than thin bolted on items