to semi answer your questions;
I installed the range afm delete device at roughly 60k miles
I installed a cheapo catchcan on the pcv line at the same time
I get about 2-3 ozs of oil and crud at each oil change
amsoil since new, 1k miles,
and am regular with injector cleaner
please note that this engine did not use oil EVER or now
I've done a lot of hilly towing the past 2 years, currently at 92k+
I hope this info will help,
Tim