400w hps, vertical or horizontal?

Hey guys, I'm a few weeks into a critical mass grow. Just 2 plants but planning on growing them quite big.

They are in a cupboard about 4ft by 4ft to ceiling hight, i was just planning on doin what i always do and hanging my 400w with reflecter as designed but have seen a grow like mine with just 2 plants where there where 2 or 3 bulbs hung vertically between the plants. would this still work with just 1 400w bulb? would i be able to put my 400 watter between my 2 plants and get more light to more of the plants to increase my yield? or should i just stick to what i know?

Thanks for any help

Stick with what you know, if you had another 400 W light then it might work out, but with ony 1 bulb 1/2 the plant will not grow very big buds.

I did this with two 2' shop flourecents with grow bulbs in them and put them across from each other. It helped with the side growth. U also rotated the plant acouple times a day though to even out the light...