I am trying an experiment with my large tank. I now have sugar sized black sand which looked great for the first year. But in time it has become full of detritus and there is no effective way to clean it. Everyone will say don't stir it up - don't mess with it, etc.. which is true because you really can't and it will cause a small cycle if you do. This excess detritus really bugs me.
So now I am going to be using this stuff called Red Sea Success Reef Base. I switched over to this in my smaller tank some time ago and like it very much. I do believe a lot of people would too, if they weren't so hung up on the sugar sized sand. It is large enough to not be sucked up so allows for the occasional vacuuming yet it is small enough that food and crap doesn't just fall through it to the bottom. It seems to be the happy medium, at least for me. As an added bonus the water has been perfect since switching over. I am converting my larger tank in 2-3 weeks after the new substrate stuff cycles.
Time will tell, but I would recommend this product.