Making the switch!!!!! cfl to HPS,, a question about 2 400w hps lights

i am planning on 2 400 watt lights for my flowering,plus my 600 watts of cfl for side cover,, how many plants can i cover?,,if they are 2-3 feet tall,, .
also....could i just grow two monsters and get a big yield? experts with first hand knowledge please...im so excited,,

i have done very well with cfl's - 2 zips a plant..i grow in soil- 5 gallon buckets, i top once for 4 cola's/// i feed very lite terra products and mollasses all the way through..any advice or knowledge of growing with two 400's i would love to pick your brain..peace..

400 watters are good for a 3x3 area, so depending on what style your growing with, you could fit in as many plants as you would like.. of course you could do a sea of green grow and have more plants per square foot, with each plant yeilding less, or you could grow three or four montsters and get probably the same yeild as the sog grow.
and yes, you could just grow two monsters as you put it, lol, and get a bigger yeild off of the two.. this is the way i've been growing personally... being in a not too friendly state, i prefer to keep the number of plants down and just grow bigger plants.. if i were in a friendlier state, i would probably think of trying a sog grow from clones in six inch pots, giving me 36 total plants for the 3x3 area,,

could i get 6-8 ounces off a plant if they were 6 feet tallwith multi colas'e

I used to use a 400w in a 4'x4' box and it worked great so two would cover a 4x8 space. You could probably fit 10-15 3' plants in there. Personally inside I dont let my plants get over 5.5' but out side i like to grow "monster" plants and I usually get huge yields off of them. Recently outside I just cut down 2 of my Blueberry plants which were around 7'-8' tall and I got around 4.5-5oz dry off each one, so yes you can get that much off of plants that big.