You are referring to Maxam Powder, CSB 1 and/or 5. I inquired earlier in the year. One of the guys referred me to the Cast Boolits forum. You can "Google" Maxam and you will find a number of opinions.
I have seen forum responses where people have crono'd various loads. There is a good deal of information out there, but be very careful and take your time.
I have done some research, wanting to load for 9mm. However, I've deemed it too fast for a handgun load. I am seriously considering it for my carbine, once I break it in.
Rio Ammunition and American Reloading retail the powder on-line.
I STRONGLY suggest you do a good deal of research before you make a purchase. I think it's a good buy for what is being offered. However, spend the time to determine if this powder will meet your needs, within safe boundaries.
Good luck.