I love MH shimmer, but I might lean toward the Powermodule out of those two.
Check this out. Premium Lumenbright reflectors, t-5, and LED. Not to throw a curveball into your thoughts, but LB reflectors are SUPER efficient. This isn't your average combo unit...Don't know if its out yet though, but I would get it in a heartbeat if i needed lighting at this point.
http://glassbox-design.com/2009/lume...mh-t5-and-led/