well . . . we got similar situation ...similar grow area , similar lights and i'm also venting in my room
true . . it's a risky business ! Now i'm down on one plant and smell
is amazing but is also very strong ! I can imagine what smell will be whit 6 plants ! ! :rasta:

But in your box u can plant 8 plants without problem !

It was better and smarter to buy a hps bulb and coll tube and extractor then Sun System 2 HPS Enclosed Ballast Light System .

In that space 400 w hps generate alot of heat so u will need a good vent system and thats a fact !