6 or 8 bulb, dimmable or non dimmable. HELP!

[Potatohead]

I just bought an eight bulb unit today, I figure I can always remove two bulbs if I want and it's not much more to purchase the eight bulb unit. Or if you like the blue look you can run a couple actinics instead of higher par bulbs. I haven't looked into it but apparently there are also new LED "bulbs" that will plug into T5 fixtures so you can go that way also.