Which lightsystems best flowering for auto

Hey guys i have a small closet and thats all i have to grow in i have a 4 bulb 4 ft t5 floro in there with 5x femenized ak47's in 5 gal pots. I have about 300 to spend and i was gonna add a upper shelf to have a 2nd setup and i was wondering if i should just go with another t-5 fixture or if there was something better for 300 bucks that doesnt get hot and is 14" wide or less. I was thinking a 400w metal halide but is that safe to put in a closet that has to be closed 8 hrs a day due to a puppy?

I would go with 400w halide because as a gambler I am you never put all my eggs in one basket, if the t5 doesn't work wonders like you hoped then maybe the halide would work better.