[creeper]

getting concrete numbers on intakes is hard, because the gains they produce can be less than the amount of power gained or lost by temperature of the car, temperature outside, humidity, and not to mention dyno to dyno

so basically (and this is my opinion) the difference in gain that you could (but probably won't) see is greatly outweighed by the difference in price. an intake is basically a filter on stick, they can design it in whatever crazy way they want and throw out all the marketing they can but in the end the ebay one is going to be pretty darn close in performance.