i wish i could help you out man, but i too am looking for some info on these viper teeth.
i am ordering new teeth for our 300U on our barko and trying to decide between the vipers and hammers. i have a few vipers i am going to install next week to see how they wear before i buy a whole set. i have even thought of putting half vipers and half hammers, to do that you have to install them in a certain order to maintain balance on the rotor.
The vipers should not last as long as hammers, but you only have to replace the tip each time which is cheaper then the entire tooth.
maybe someone can chime in that has used these teeth.
Also quadco and king kong make teeth for these heads.
justin