I actually would go larger on the tent. 8'X4' with two doors, then divide the tent into two rooms. Flowering and "work room". Work room is were you would hang some 4' T5 florescence. This is were your mothers, clones, and those waiting to get into the flowering stage. I use a simple drip system in this room, and an Ebb and Flow in the flowering room. I use a 430 watt HPS with blue spectrum in a Sun Systems XXXL Hood with 6" vent and electric ballast.

Whats nice about getting the 8x4 tent right away is that it leave you room to expand. Just get a extra 4x4 and make the extra tent your work room. This doubles the size of your flowering room when you get a second hood and ballast.

This works fine. I rather have 3 430 lamps instead of 2 600. More area same power consumption, Thats all. Not much heat means closer to the plant, which means less light loss.

I also notice on one of the photos that an air intake is high. Usually air intake is low and air exit is high. Hot air rises and you don't want to pull in warm air just to get it further warmed by bulbs. also Think CO2.

They beauty of all this is Portability. I can take down move across town and set up in hours.