The dump valve issue is age old goes back years.....the actual question at the top refers to reliablility and performance rather than JUST performance or thats how I read it. In my opinion and its just my opinion if I was building something like a mint sierra saph which was to be standardish I would fit the standard re-circ dump valve. Theoretically the dump valve should improve turbo lag and defo does prolong the life of your turbo, I was personally only trying to advise in a positive manner not fuel an age old debate....