Very cool, thanks for sharing! I am about to do a similar switcheroo, a WH7 driving 54W T8 bulbs. Still waiting for the reflectors to come in, for some unknown reason UPS ships them all over the place instead of to me
Does the WH7 really get hot? I wouldn't have expected that, especially with 28W (?) bulbs. I am planning to mount mine outside of the canopy, in the back (invisible).
I used to be a firm believer that 1 Watt fluorescent light = 1 Watt fluorescent light, boy was I wrong. I will replace all of my T8's except for one pink "grow light" (Florasun) with T5's, it is a big difference.
I wonder if I could drive both T5 and T8 bulbs from the same ballast... have to try that.