I have two tanks and went with the BDBS in the 10g. Looked great. Very much liked the black and shimmery look it had. Made everything pop as far as looks go. Really liked it to start off with.
After a while noticed that my nerites would try to avoid it to a degree. At first thought it was my imagination but noticed in my bigger tank with sackrete commercial medium sand they would burrow and cut across the bottom edge of the tank cleaning the glass under the sand layer. Sometimes spending what seemed like days half berried in the substrate eating stuff. I just ended up changing my 10g over to the same sackrete sand. Dont regret it besides that I kind of wanted the black substrate. Just to cheap to go buy more sand when I still had left overs from the $10 100lb bag I got to do my 40B.
Anyone near Everett WA that would like a couple unopened bags of BDBS by chance