Thanks, great info.
Check out the link to my grow log below, it has just a few pictures where you can see the lights. All bulbs have reflectors and all bulbs are 1 to 3 inches above the tops. Also, the walls are lined with reflective insulation material and are very close to the plants so the light doesn't have to travel very far when reflected. Not sure what else I can do, I guess I feel pretty good about it, especially with the continued LST that keeps all main tops very close to the lights.
Still, if I could really get 25-50% more by using a 150w HPS which actually uses slightly less power then that sounds like a bargain and I will probably do that eventually.
Anyway, in a month or so I guess we'll know exactly how much I got. At least pretty close though I don't own/need a scale.

Lastly, I'm planning for my next grow to be in a Hempy Bucket (passive hydro). I wonder how that would do with the 150w HPS / Hydro combination!
If you don't know what a Hempy grow is check this out or just Google "Hempy Grow".
HomeGrown420 - The Hempy Bucket