I like using the screw in bulbs because it gives me a lot more flexibility to fine tune the amount of light, and where over the tank its concentrated. I have 8 bulbs in my hood. Right now I have 75w replacement bulbs in there (I think they are actually 18w), but I'm planning on getting some 85-105w (actual watt) bulbs soon. I'm not dosing co2, but I've been collecting everything I need to, and will start dosing once I get the new bulbs.
I have about 1.2wpg over this tank, I dose with Flourish, Excel, and Iron, and have it pretty well stocked. Here's the plant list:
Amazon Swords
Wisteria
Baby Tears
Cabomba
Red Ludwigia
Un. Ludwigia?
Hornwort
Marimo ball
All of them are growing fine under the current conditions. The hornwort and wisteria are growing (literally) about 1/2-1" a day right now. I'm going to have to start trimming them back pretty heavily soon.