recently i bought two pieces of blue diamond to try and it covers very well so i used less. on piece lasted me about a month and a half with minimal removal of the higher edges once in a while. but i will say this, i noticed no performance advantage over good old blue masters chalk. i also have a piece of pre flag blue masters. again, i think it covers beter so i use less, but as far as more perfomance, sorry that's all a myth. silver cup seems to not cover the tip as well and therefore i have to chalk more frequently and when i am done playing it looks like i have been playing with a smurf's weenis and he let loose on my cue and hands. therefore i think that stuff is garbage. however as far as chalk goes, as long as i constantly put it on the cue there is, again, nor real performance gained or lost. just my ramblings.