I dont use them, but Ive read about them quite in-depth. Here is the finer points of both arguments. Moly, by virtue of its friction reducing abilities, slightly increases velocity in a comperable load and does it with SLIGHTLY less pressure reduction which, because of the two factors just stated, also means your bbl heats up slower.
On the other side of the coin we have complaints that the moly is sometimes harder to clean from a bbl. Some claim that the reduction in pressure and increase in velocity is so minute as to counter its bad points. It is also said that, with moly bullets, a bore must be prepped after cleaning, usualy meaning a fowling shot or a liquid moly prep.
My take? I pass on them. I dont do high volume shooting so Im not worried about heat. Velocity is not really a huge point for me either. If I were to go with an "exotic" bullet then the copper solid hollow points like the Triple Shock impress me more. I guess it comes down to how important certain aspects of what you are trying to achive in your loads is how you should decide.
Brian M.