T-5 HO lighting is adequate and efficient if you keep plant material close to the lamps on the full length of the tubes. You can put the leaves as close as 1" without a problem. I use a metal screen over the lamps to do this. In most of my grows I now use 400 MH where I used to use the 4 x 4' T5s. I now use the T5s with grow or veg tubes for supplimental lighting.