This was the first product structured to time release testosterone. The PROPIONATE ester, in theory should release it's testosterone quickly, and thus becomes active after one day, but through the series of the other three attached estrified-testosterones, remains active for another couple of weeks.
This time-release action is why Sustanon fetches a better price on the black market than other types of testosterone. Anecdotally, it may cause less water retention than it's less popular brother Omnadren. Since, in the end, Sustanoln is simply testosterones, it provides improved muscle pumps and better post-training recuperation, as well as an elevation in aggressiveness toward pushing heavier weights in the gym.
250-1000mg weekly is very typical with this drug, with the average being around 1-amp per day; as with any drug, some used higher dosages. Excellent results were always realized with a dosage of 500-750mg every 7-10 days. Women should not use this product, of course , and none have reported doing so, all due to virilizing effects.