It has been another season since I installed the lights and I have to say it has been a success. Not one breakdown or manufacturer recall during the year. 
I have to admit that I am a little bit surprised because of the rough environment. Lots of heat, dust and vibration, but so far so good. The work in the fall, during the leaf collection process is especially grueling.
Here is a picture of my gasoline powered - self propelled - rolling flashlight, about to be cleaned and put to bed for the winter. 
The 4 MR16’s with 8 Nichia 119’s each on top and 4 XM-L’s on the bottom. Notice the tint difference between the Nichia’s and the XM-L’s
The XM-L’s were added here: Light Bar Build 2.0
