IF your plant has multiple growing tops, allow for more root space. Also, remember to re-pot on a good schedule to avoid soil stagnation and pH drop. 0.5 g per watt per month is a very good grow; sativas are already difficult to grow indoors and I would calculate your yield at about half that, to take into account grow skill and the species itself. But really, yield predictions are difficult before you get a very repeatable routine worked out.