i deal with alot of dart heads for customers there is no free lunch on heads most of the big power guys we are useing Pro 1 cnc heads and there as good heads out there as darts RMS .Profile. AFR . are the makers that i would use if not for me getting the darts as i like money staying in MI or at least the USA. if i can ...as a engine builder i under stand the fact that there much cheaper heads and many guys want THE LOOK i given much thought of building a 496 crate engine with all the lower dollar stuff were the rub comes in as alot of the stuff is not worth the time getting it to fit