HPS is not ideal for plants in any way. It has very low PAR, and used alone the results speak for themselves. If you compare equal wattage HPS to MH+HPS during ANY cycle the MH+HPS pair significantly outperform solely HPS, watt for watt.
Enhanced MH are nearly equal to CFL bulbs in terms of Lumens * PAR(as a decimal percent).
That's what the entire efficacy of any bulb for plants comes down to: Photons(Lumens on a grander scale) * PAR(as a decimal percent eg. 0 to 1).
Thus the 'wasted gas': lumens - (lumens * PAR decimal).
Well I actually grow with Floros, then MH, then HPS as this is the best method that I have found. It works better for me than any other method I have tried or seen. I'm a results based grower.
I use T5's and CFL's for little guys and about 1/2 my veg. When the penetration is too poor I use my MH. When I go to flower I use 2 HPS's.
I'm not going to argue about whether or not CFL's are viable. They work fine for smaller operations. But when you're trying to grow 10+ plants it gets pretty damn hard with CFL's.
LIke I said, a matter of results and you showed more about PAR and Lumens, nothing about penetration, light degradation as a square of distance, etc.
CFL's are awesome until your plant's are 3 feet tall and you have 12 of them. Then it's a fucking nightmare. 30 CFL's or 2 HPS'? Just a matter of management, ease and overall performance. I'll pull just over lb in just under 3 months. That's hard w/ CFL's...not impossible, not impractical, not going to argue their validity, it's just more difficult and more work.