thats a very good price
but check out one of the digi ballast, their smaller, use both mh and hps bulbs, run cooler ect
was goin to give this link but didnt have the 400s up, only the 600 which i bought
eBay Store - growrite: Grow Bulbs, Complete Grow Light Kits, Compact Fluorescent Grow Kits
good prices to in my eyes and a good warranty too