You get about an extra 40w with the 4.36 but its like a $150 more. I am not a huge fan of these kits cause of the cost. I just purchased a fan kit and uv tempered glass from them for like $65 and I am installing a 70w MH in it myself and still keeping the 2 x 32w CF lights. I should be good with that to put whatever I want. Didnt go with the 150w cause of heat. Whole thing should run me no more than $175 to do