Gene, I am using 4' LEDs as well along with my many T5HOs. I have one shelf that is a commercially built light shelf, the others are wire shelves. I installed some of the 4' LEDs right beside the fluorescents under the reflector on the commercial light shelf.
The cost of the 4' LEDs on Amazon is to me quite reasonable and they are easy to put up.
The plants seem happy, the African Violets are blooming.
But I am not going to complete the changeover until I see the results a little more long term, right now the cacti/succulents still are under sunlight and T5HO exclusively.
