As far as yield to expect...I am not sure....Never done this inside...I am testing this all out. I dont smoke all that much but LOVE to grow it...I have my medical card in Maine and am going to be a caregiver....concentrating on vets with PTSD.....so I am just getting started...outside I have no problem...but inside I have realized I need to be mother nature....wind,rain,temp,humidity etc....this is all new to me...I think I will go with a 1000 watt system without the cooling hood....I am growing in my upstairs in Maine and we have COLD winters and the stairway has a door on it to keep the heat downstairs in my house...I can regulate the temp of the room with heat ducts on the floor...I plan on having a carbon filter sucking out the heat and smell to the outside and a 6inch duct fan on the floor sucking in cool air.....sound ok???
O would personally go for a 100w with the cooling hood my friend.
Its a personal choice though and the 600 would work as would the 1000w without the hood, I just believe you would do better with my original idea.
My 600W MH raises the temp from about 71F room temp to 79F, and that's with excellent ventilation from a 590 CFM fan with a carbon filter (the room is 4.5'x4.5'x7'). Just an idea of the heat released by a 600W