I was having trouble with high gravity beers not carbonating properly after bottling.(especially during the cooler months in my drafty old house) Danstar CBC-1 has solved that problem completely. I've started using it in conjunction with the usual amount of priming sugar whenever I bottle a higher gravity beer and it works like a charm. Does not seem to impart any flavours that might compete with the original yeast used on brew day. Worth the extra couple of bucks per batch.