Need Help with Sea Of Green Method

I am currently setting up a grow. I intend on just allowing each plant one huge cola. My current plan is doing four plants per square(ppsf) feet in 6"rock wool. Heaight is not a concern, I chose SOG simply because I have done grows with 5 gal buckets and huge plant and was not at all satisfied with the result after vegging for 2 months. I have a couple questions,
1. How long should I veg for this set up, since they are going to be quite close?
2. With that said should I increase number of ppsf for a better results of just one cola? (I have read amazing results with 16 ppsf with no veg time is it true?)
3. Should I use a bed on the tray; ex. (hydroton/coco and perlite)?
If you need anyother details just ask. Please all information will be appreciated and I want to thank you in advance for your help. I am not a newbie grower however I am new to SOG.

i veg for 10 days (once they have developed a couple new sets of leaves), then flip them, they grow very quick, then i trim off alot of the side branches, try to keep it one big bud. pretty straight forward.