how many plants to put in a 4x4x6 with 600 watts for the best yield?

I was told that in my 4x4x6 with 600 watts that i could put 25 clones SOG style in soil and veg for a week and a half and go strait too flowering but i dont know if that guy knew what he was talkin about. Any opinions would be great as this is my first time growing and have no clue.

25 is a bit cramped, I have a 5x4 and can do 12 with 2-400 and no problem but 8 is a better number, unless you have just one big bed of soil that measures that dimension than no problem just depends where you space your plants.

i have found that a 600w is god for about 6-10 plants depending on the size you grow them to.
I have a 5x5x7 and 6-8 plants under my 600 is working great