A lot of people like the MH as do I in some
apps like the tunnel and use the 320 W Scottsdales . Some use them in opposite ceiling crners to get the sides and tps of the cars. Since Straight down on the top in a bay may not illumoinate the lower sides and wheels unless you have really reflective walls. the above system has 640 watts total.
In my bays where the walls are not really reflective - Maybe one day will spend the $6000.00 - I have 4 , four foot double tube wet encl. HO flurescents mounted horizontaly at about 8 foot height, each about 2 fet in from the end of the wall. each fixture is 120 watts. - 60 each bulb. Does a great job and is less expensive to operate than the MH. If I did it from scratch I might figure a way to run opposite corners all the time and use a motion sensor for the other 2 or tie it into the meter box use. I don't think that wwould be practical with an MH setup.