I finally got a set of Combo 'Blues' a couple of months ago. Were easy to install, although I upgraded to a longer & thicker gauge of wire & an inline 30 amp fuse. The supplied wire seemed a bit thin & short.
I am very happy with them. They were put to the test on a recent trip to Thredbo. They prevented a few animal suicides on the road. They have great range & give off a bright white light. More than adequate for my needs. Great for the price - $150. They haven't moved at all either.
They haven't effected the cooling too much yet, as they don't take up too much room. It hasn't been hot either. The temp gauge did creep up more than usual on a long 4km hill climb, but was nothing to worry about. I'll have to have a Stockton day in the sand to test.