A Friend of mine gave me a cube because he didn't like it. Pretty much what I use it for, altho it won't make a bit of difference.
My tips are always cleaned after games, so yes, I put on a base coat and then use Pre Flag. This only happens on occasion when I happen to use my Bar Cue for messing about, because the Kamui is in the single case with it.
Magic Chalk is every bit as good as Blue Diamond. I can use either one and make several shots with one chalking. That is, if one is comfortable in playing and disrupting your regular Pre Shot Routine by not chalking every shot.
The very first time that I used it, it happened to get a little dust under the ferrule and I had to clean the shaft on the lathe as this stuff gets on and can be difficult to get off like regular chalk.
There is absolutely no chalk on the face of this Planet that is worth 30 buckarooinies.
It is, or was a Gimmicky Fad that players may try one cube and then if they haven't set it on a shelf forever, they will likely never buy another cube.
I have a few boxes of Diamond left over, over a Gross of Pre Flag plus a few boxes of Magic. RJ sent me another few boxes of Magic a few Moons ago so that is what I prefer.
For the cost and the quality of that, it is worth stocking up a bit with Magic and not worry about any other brand like Predator and so on. I tried a Friends Pred chalk and would have to say, not too bad, but then, only slightly better than Master chalk.
I find that the Magic is slightly grittier than Diamond, which is good because one can make a serious mess with Diamond if you chalk too vigorously.