Well i have one plant under my EXT 300 and only 12" of clearance from the closest bud.....the plant is 28" x 28" x 30" and is stacking up like a champ......i wish i had about 4 to 6 inches more of clearance so the footprint woud be a little wider, but as of now dont see much difference in the size of the buds on the outer edge of the footprint....if you dont mind i will post a pic of it tomorrow.....i am hoping for about 8 oz off her.........maybe more if her buds keep growing so well.....but i will be happy with anything over 5 as that is my best so far off one