Hey, im not saying you are wrong, it IS safer to have bigger injectors.
My point is that i know a gtr owner who runs standard injectors, n1s @20psi and has run an 11.7@121mph 1/4 mile, and i didnt state it before, but the injectors were running at maximum 90% duty cycle. seeing this is enough evidence for me to not change the injectors unless running more than 20psi..
but then again, since there is a few different types of N1 turbos, for your car @20psi, bigger injectors may be needed in your case.
and yeah i have read about that particular performance shop and dont agree with what they do either.