what size tent is it, im sort of wishing i had gotten the 300 the 240 is fuckin bitchin but in my space the outside ones grow just a cunt hair slower than the ones in the center. Hence wishing i had the extra 40w and the wider panel. Mainly just the wider panel i dont think the watts is going to make too big of a difference but the footprint size of the 300 vs the 240 is way better. The 240 is still handling though. Lets talk in hid terms its like if you bought a 400w hps instead of a 600w. You would be much more satisfied with a 600vs400. Same with these two panels i would think. Next one i get i think is going to be a 600w. MAYBE....