I've got this unit mounted on my Fresh Breeze Monster.
Installation was strait-forward and pretty quick. I've got about 60 flying hours on it and it has proved to be trouble free. It operates off a couple of triple A cells and turns itself on when the engine fires up and shuts itself down within 5 minutes of the engine shutting down.
It has a handy memory function that allows you to pull up the max temp in the last 'on cycle' for CHT and EGT and I usually note this in my flight log.
I believe the EGT saved my engine last fall when the cool weather caused my mixture to lean out and the EGT just crossed over my set alarm points. The display started flashing LED's at me and got my attention in time to bring the temp back under control before things got ugly.
Of the 3 measurements (RPM, EGT, CHT) the RPM is always displayed and the remaining display can be cycled between CHT and EGT. This is one of the few things I would change if I could because I have multiple tach's for viewing and would really prefer to have both EGT and CHT visible at a single glance.
Overall this is a sweet little unit and I couldn't tune the engine worth a damn without it.
I've gotten to the point that I would be very uncomfortable flying without it.