I have been forced to abandon Dow 321, not that there is anything wrong with it, but because Dow jacked up the price -- it's currently going for $46 at Enco.
Soooo ...... I tried LPS 842 ($20 at Enco). Compared to Dow 321, LPS 842 is thinner and runnier. But I like that it dries faster than Dow 321. I wouldn't say that it works better than Dow 321, and I'm not even sure that it is equal to Dow 321, but it works satisfactorily, so for half the price of Dow 321 I can live with it. From now on it will be my new standard dry lube, until something better or cheaper comes along.
In other news, I've been experimenting with synthetic 2-stroke lube and with moly grease. I apply a tiny bit to the underside of the sprue plate (using a q-tip), concentrating on the hinge area, and wipe off the excess before attaching the sprue plate to the mold. Both help. The 2-stroke lube is a bit thin and doesn't last long, mixing it about 50/50 with moly grease seems to be a good compromise. You can use the 2-stroke lube in addition to a dry lube, but be aware that it may dissolve some dry lubes.