For super hard tips on a break cue, ( I have a Lucasi BBII w/ Phenolic tip ) what is the preferred shape of the tip? Also, what are the better ways and tools to shape these very hard tips? Should the tip be more flat? Nickel shape? Dime? What do you do? What do you like? Why? Thanks. I look forward to the thoughts of those here with experience with different break tip shapes.