Emily: I have several of Gardener's Supply T-8 bulbs (as well as a couple of their table top and floor stand). These are several years old, before the T-5 technology was common. I have to say that the quality has been excellent, and Gardener's customer service has been great.
When I added additional shelving units, I found some great ones at Sam's Club, and took advantage of the cosmetic "seconds" T-8 fixtures that GS was selling last year. I really like the GS light fixtures because they have 3 bulbs, and a nice wide hood to give me coverage over the entire width (18") of my shelves.
This year, I bought my first T-5 fixture (not from GS)--it has 4 bulbs and I'm using it over my large herb pots I'm overwintering. The light it puts out is amazing. I don't think you will regret your purchase from GS. Even my APS systems that came with my shelving units are still going strong.
