This is seemingly an old thread, but I'll add my two cents.
Some of the additional advantages of the Staun Tyre Deflators:
1. Fastest tire deflators on the market.
2. Easy to use, no tools required.
3. Extremely accurate; within .o5 psi of set pressure.
4. Can air down all four tires unattended, simultaneously.
5. Can drive a vehicle while tires are deflating.
I bought my tire deflator https://mechanicguides.com/best-tire-deflators/
5 years ago for R500 and have used them very often. I prefer to use them rather than the ARB type in that, they are preset to 1.5 Bar, so when I arrive at the venue I unscrew the valve caps and screw these units on. Then I go about chatting and greeting everyone, maybe some admin etc all while the tires deflate to the pressure I want. The only time where I will deflate more than 1.5 is when I do sand driving, but then I have the badger tire deflator for that.
What is nice about the Stauns is, you hit a gravel road... you stop, screw on these deflators and you drive further. Then a few km's down the road or at your destination you just unscrew and replace valve caps. This way you have a nice and soft ride on gravel roads and are at lesser of a risk of being hijacked etc as the time you spend standing beside the road is very little
All the best