Customer testimonials without complete names or expertise, is what snake oil salesman wave around. And to top it off, one testimonial (Vinny H) is from a FASS dealer who sells their products at his performance diesel business . The others waffle on like all magical fuel device testimonials, "they feel instant power," or "it runs crisper" lol. But no evidence or dyno runs. Just crap you could never challenge legally.
You are not doing yourself any favours pushing this junk.
ps I have seen the videos of frothy diesel.
How about asking the FASS team to join MUD and we can ask questions directly.