This is one users review:
"For those interested, mixability/texture of Carb Slam is top notch. It is a very, very fine powder (i.e. no grainy/gritty texture) and is completely water soluble."
I have not yet used it myself, but thus far people like it

It is the same carb source used it the olf Vitargo (I believe they recently switched to a barley carb surce).