I bought one of these and it arrived today
I'll use it tomorrow and write up here whether it's any good. It cost £19.90 (c $32) including delivery.

 

I bought a cheap Chinese HUD unit to play with and it also arrived today. It looks and feels OK but the instruction booklet is typically rubbish. Does multiple tasks though including codes but I haven't hooked it up yet but when I've tested it I'll write up here whether it's any good or not.

Car HUD Head Up Display KM/h&MPH Speeding Warning OBD2 System Sale-Banggood.com

Hooked up the HUD today and went through the initiation scan as initial setup. All works according to plan and ready to rock. The only viable place to mount it was on top of the instrument binnacle and although it's slightly curved it sticks to the pad there OK.

 

So I tested out the Bergen battery tester today and it certainly works fine and what it told me was both of the twin Pajero batteries were shot, one just marginal and one scrap. Looks like two new batteries are on my budget although can't complain as the 2x Bosch Silvers have lasted 8-10 years now. Hope the next pair last as long