how many m2?
2 600's would be amazing in that area. get digital ballasts. t-5's or cfl's for your "daylight" blue spectrum on the sides. just keep the temps under control and you will not be dissapointed.
Mate slow down... first of all are you living in apartment or a house? and where is your setup. Second how good airflow you got, and third, Do you want to that high in electric bill... i mean cmon 2 x 600, its 1200w...
mh for veg will work instead of t-5. you will need some sort of air conditioner to cool the area unless you live somewhere real cold. 1200 watts won't raise your bill that much. find out your local KwH fee and there is a lighting sticky that can help you calculate the exact cost
here is a easy to read fairly accrute power charti didnt think it would be that much either, i think he just wanted to worry me!!! haha
here is a easy to read fairly accrute power chart
http://www.n-g-w.com/ngw/literature/catalog_powercost.pdf
also veg under 1 600 in smaller pots then as you transplant and need more light plug the other in
ohhh cheers man, how many veg plants do you think i could get under 1 600mh?????