Quote Originally Posted by Stormhammer
One of them is not better than the other. All BOV's are relatively the same in performance. It all comes down to what sound you prefer in the end.
Not entirely true. Lower quality valves will have a tendency to leak, and you'll lose boost.

Greddy, Perrin, and TurboXS actually make really good stuff. Greddys street BOVs sound pretty unique, as well. I know the Perrin ones are designed for something like 120lbs of pressure.

A BOV is something you want to spend the money on, to be honest...seeing as you probably have a lot of money in your ride.