What do you think about aftermarket parts?
 

I'm about to replace some things in my car (my fuel pressure regulator is one of them) and I've found one aftermarket FPR from an unknown brand. It's new but it has 6month warranty only. What do you think about these aftermarket parts from unknown origin/manufacturers?

I know that the aftermarket alternators made in China are very problematic. Which other parts do you guys know are pure crap?

Fuel lap or nothing.