Electric superchargers, Do these really work? Options

[bdawgbp1]

I have been curious as to the functionality of the electric superchargers on eBay. I am very skeptical of this because I can't see how some $40 to $80 plastic "squirrel cage fan" could be of any benefit. The description says that it flows like 500cfm of air, which would be equivalent to 2-3 psi boost - so it says. If these really worked wouldn't we be seeing these on race cars or on the street scene? IDK, my buddy swears by this thing as he bought one for his car, a Honda Civic, and said that it worked so well at wide open throttle that he bought a second one and custom fabricated a custom "Y" intake tube to bolt both onto. He siad he put a K&N cone filter on both and said it's almost like having a low psi turbo on his car at wide open throttle. I kinda though the idea sounded like some bull**** to me but I just wanted to know if anyone else had experimented with these things. It seems to me that this thing, even with a high flow filter like the K&N, would restrict the airflow coming from your CAI due to the offset to the side of the filter (where just the CAI has the filter straight on the end of the intake) and the air having to pass thru the "squirrel cage fan". Any thoughts out there?