Good day to all.
Slowly I'm becoming part of the family. The past weeks I've collected some very nice, nearly new GHL equipement. Some luck was involved.

This week I have an appointment with a reefer that's quitting the hobby. He's selling some Mitras. We agreed I could check the lights.
However, since I've never held them in my hands or got to fiddle with them, is there an easy way to verify time that they've burned? The PDF manual doesn't seem to like me. (Or I'm just clearly missing that part when searching through it...)
It's 3x Ghl mitras lx 6100 HV, these modules were later replaced with 6200 HV. Time of purchase of the fixtures, and afterwards the modules are known. With an average of 10hours/day the claim of 22.000hours should be correct.

For the moment there's no reason to doubt the person selling them, but these are some expensive lights. I'd like to be sure.
Apart from the hours, and visible inspection, is there anything I should surely check?

Any information is greatly appreciated.

Thanks!