They are not bad at all... On cars that I have seen with these intercoolers they experienced minimal pressure drop, and much cooler intake temps so in my eyes they do exactly what they should do... You also have to take into consideration that these companies do not make the cores, they only design the end tanks... I'm sure they buy cores from a reputable source because those that I have seen looked very good, almost comparable to those of a spearco or precision or any other highly priced intercooler...

You always have the option of buying it, get it pressure tested, then put it on the car and see the results for a while, and if you dont like it, you can throw it right back on ebay and make most, if not all of your money back.....