Our 2 Cents,
We have a grow op large enough to experiment with most commercially available horticultural lighting. We've done these "tests" side by side, with all other variables identical. The purpose has always been to identify any better alternatives to HID lighting. By better, I mean more efficient, cooler running, faster and/or more robust growth, with little weight given to initial cost. With 20,000 watts of HID running, even a small increase in yield and/or reduction in running and cooling costs would pay for the initial cash outlay fairly quickly.
Unfortunately, HID is still clearly the best choice for us. CFL's just don't have enough canopy penetration. Optimum growth only occurs in the top 12" of canopy. This cut our square footage yield by 70%. The node spacing was twice what it was with HID. They're just not bright enough. I would go with a tiny HID before any CFL on the market.
LED performed better than the CFL's, but still miles from HID. We used them in both veg. and flower stages and saw differences in both.
I haven't tried plasma yet, but will soon. I can't help but anticipating more of the same.
We are still burning 8-1000watt MH's, and 12-1000 HPS's. Ironically, pretty much the same settup I started growing with in 1994...just a few more lights and better bulbs. Oh...I do like to use T-5's now for cloning and the first week of veg. Of all the advances in indoor growing, lighting seems to have hit a cieling some time ago.
To anyone getting started, you just can't beat T-5 (clones, seedlings), Sun Pulse 6.4k Metal Halide for veg, and High Pressure Sodium for flowering...I like the digilux bulb. I should mention that I use the 6.4 Sun Pulse for the first 7-14 days of flowering (strain dependant). This helps keep stretching under control and improves node spacing.
This is just what works for us. I'm sure other growing styles will have better success with different settups. I am sure, though, that you will not be dissapointed with these lights.