Use something else, it would work out cheaper as well. Try increasing the sust or use another ester. Personally I would recommend buying some prop and shooting the sust once every 5 days and adding the prop in there on an eod basis.
Go ahead and add it in. It won't hurt and the dht really seems to boost the gains...but harsh on the hairline. At about a dollar/amp its a relatively cheap cyp/dht combo to add to a cycle...but I wouldn't base a cycle around sten.