Having the HPS and MH in the same ballast sure helps with usability and space. You sure get the use out of the ballast, as compared to using two. Saving money was the part I liked about it. When your buying 3 or 4 or more, it adds up and in the long run your saving even more money. Complete kit is nice too, not having alot of work to do when you get the ballast to its final destination, it plug and go. Well worth the coin spent.