Hello B I'm affraid where lights are conerned I'm only know the one I use and to be honest I no next to nothing about that

Before I bought it I read and was told that the best combination of lights was a Matal Halide for vegitive growth and an High Pressure Sodium for flowering.
Well I just went to the growshop told them what I wanted and they sold me the set up.
The ballast thingy can take both sets of bulbs, so when I've finished on the vegitive growth I just unscrew the MH bulb and screw in the HPS bulb and start 12/12.

I know the guys on here are always on about different types of lamps so I bet they can help you.

Heres a pic of my ballast thingy, oh, the small box that is with it is a relay switch, which stops the timer from melting.

The set up runs on 400 watts and they are quite exspensive to buy but I think they can be found cheaper if you shop around a little



love mand xxx