Some thoughts
a new grower can have 16 plants under 1000 watts (4x4) - (5X5)
grow in soil and make sure you have an exhaust fan to take the heat away from your lights.. keep the light close.. 12-18 inches from your plants.. this will require proper heat management..
you should use 1-3 gallon containers..
make sure you learn about pH ing your water...
and you will be fine...
pH Water - See More Buds
yes 2 - 600s is better, especially if you can manage the heat very well and get the lights close to your plants....
cheers