I did not like my Grimes at first, but now that I am getting experience adjusting it properly, I like it more. I would probably install it.
I fly night XC about once a month. In my opinion the key to safe night VFR flying is getting the ambient light inside the cockpit down to the absolute bare minimum necessary to see required indications, which to me are airspeed, altitude and nothing else. That minimizes glare on the inside of the windscreen and allows your night vision to sharpen, so you can see every detail outside the aircraft. Only red, NEVER white light. Lessons I learned in the military.
The Grimes can be set to red or white, dimmed or brightened as needed, pointed where you need it, and will stay where pointed. The dimming switch is very precise, so you can fine tune the intensity. Most importantly, it is wired to ships power, so battery life or state of charge is never a concern.
The major weakness of the Grimes is incandescent bulbs instead of LED. Really surprises me that there are no good certified LED options out there. I considered putting an LED bulb in my Grimes, but am concerned the dimming would not be as precise.
Back in the old days, when we flew with paper charts, a Grimes or something like it would be essential. Nowadays with glass panels and iPads, not really sure what you would need to illuminate.
I am considering installing post lights on a dimmer for my airspeed and altitude. If I do that, the Grimes is probably redundant, but I'll still keep it just in case needed for troubleshooting.
From a legal perspective, my AFM lists the cockpit light as "standard" instead of required.
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I’ve done that. I’ve also grabbed the throttle when needed trim.