lets say i did switch to hps

I have a space for flowering that is 60" by 24" by 48". Lenth depth hight. I'm using cfls right now on 2 one foot pinched plants and I'm thinking towards the future. Do you think a 400 w would do the trick or better to get the 600. Or still yet two 150 w?

honestly it seems on this site the higher watt hps lights do really great work so i would say 600 would get the job done for you sir

If your grow space is only 48" tall you will need to do some serious lst for a 600. Id say get like a 250w or 150w or two. I dont see a 600 or 400w working for you unless you ran a air cooled hood with a good size fan cooling it and trained the plants to grow sideways. Even then I dont see it working well.

Figure 12" for the light and hood, a min of 12" between the bulb and top of plant, and a 12" of pot (could use 6" square pots Only leaves you with 12" to 16" of actual vertical growth space.