i am a PPG certified painter with 40 years of experience.
there is a light year difference between the $16 HF gun and the $180 one.

i used to use the $16 HF gun for PRIMER for years it works OK for that. i have used it for regular painting a couple of times. i didn't care for it. it doesn't atomize the paint to my liking.. now the shop has a 3M changeable end primer gun they want used. it's and much easier and cheaper to clean.

i haven't used the HF black widow gun. i have talked to another painter at a PPG training certification class about it. he liked how it worked.
i HAVE used the next level down gun for painting a couple of times. it worked pretty good. in a pinch i would used it again. i still prefer my DeVillbis TEKNA gun over the HF one. especially for the clear coat. i spray the newer ultra high solids clears used today with a 1.2 tip. this in not available with the HF guns. i use the 1.3 tip when painting the water base coat.