Cheap ripoffs of the brand name

has anyone ever seen products that say something like greddy style or you can tell its some replica or ripoff? does anyone know if those products even come close to the brand names or are they just cheap ripoffs that waste your money? if you dont know what im talking about, go to ebay and search for automotive parts and youll see a bunch with "style" attached to the end

Well, it depends, if you mean intakes, exhaust lips, mirrors, etc... the fitment is usually off, and they end up sending you some universal version they doesn't work on your vehicle, or is ever so slightly off because there is no R&D behind it.

Other stuff like rims, ECU's and parts like that depend on who makes them. For example, Rota, they make copies of other manufacturers rims, but they are well made, cheap, and durable. But say a "Mugen" chip in an ECU, all the do is base fuel maps on race spec cars, and dump a lot of fuel, yea it's a little fast in some cases, but others can just bog your motor.