I would fill the tent up with 4 x 600w hps, with 9 plants per light, aiming for around 60-70 grams per plant.
It's basically a plant every square foot, centered under each 600w. Give the plants a little space in betweed each group of 9 plants.
Much more even distrubution then 2 1000w bulbs. And this would allow for raised light so it would be easy to get into the tent.
And you can get your lights closer to the plants increasing their efficiency.
The growth should be much more even than with 2 1000w's.
If I was to use 2 1000w's, I would get 2 adjust-a-wing large reflectors, with super spreaders, and an 8 inch inline fan for exhaust. The reflectors have a 96% reflectivity, and are meant for 5'5" x 7'5". This would be some very uniform growth you would see, and as efficiency goes, most other reflectors only give out 86% of the light reflected off them. Extra 10% light coming off the reflectors, as well as reducing the temps of the center hotspot by splitting it in two for each adjust-a-wing.
Another benefit is not losing 7% of light through the glass, and further loss from the actual cooling of the bulbs from the air cooled reflectors.