I don't use it, but will switch from the Kent AB product I currently use, once my bulk supply runs out. I think all the two part chemicals work the same, as is give you virtually the same increase in Alklinity and calcium. But, the B-ionic has less initial effect on pH. When I add a dose of the Kent product, pH takes a quick little spike. B-ionic will have much less of that spike. Since my main alk/calc dose regimine is from Limewater, I tend to have high pH and the addition of the Kent product can be a problem.
But, for those whose main dose regimine is a calcium reactor, thier pH tends to be on the low side so the Kent product may be better for them.
Randy Holmes Fraley has a good article discussing the different calcium and alklinity suppliments systems and which are better for who.
http//www.advancedaquarist.com/issues/feb2003/chem.htm