Humboldt Hydro sells 2 diff. ones from Intelli Drive 6 & 10 rpms. The 6 moves slower than the ten, about 7 1/2-8 1/2 min. per cycle to go 9 ft, the 10 about 5 1/2 to 6 1/2 min per cycle for 9 ft. however both have up to 60 sec delays at the stop points to even up the overall time spent over the plants. I just finished looking at >5 diff hydro shops and they seem to be the cheapest, HGT may have free shipping but they were by far the most expensive at around $230. Humb. Hydro. without shipping was 144.00. Far less than another light with bulb and ballast, and don't forget to figure out the elect. Plus you can add a longer track as well as a second light to the system. Needless to say I'm going to try it with my new room setup. GL HH PS: If it's good enough for FDD it's good enough for me. lol