I use a 2 ft 8 bulb T5, I'm in a small closet with no venting. The thing puts out almost no heat, I can put my hand almost touching the bulb and not feel it. If your looking for weigt HPS will kill it. That said I did an LA woman all the way through flower and got an OZ of the best bud I've ever tasted in 35 years.
This time I topped and should be able to get hopefully 2oz. If your looking for simple and easy they work, if your looking to maximize yeild don't flower with them. good luck