The K&M 21312 is a basic carry bag for speaker stands. It fits two speaker stands (plus one or two smaller mic stands if you try). The zippers are not the best in terms of opening and closing, but they haven't broken so far. The bag itself, on the other hand, has ripped from both ends after about 3.5 years of active use (about 100 gigs). For the price, I guess it's okay (10?/year). Still, I would have liked it to last a little bit longer.
I've worked by way through many bags and cases over the years and have found the K&M gear to be excellent. They have been designed by people who actually understand what they will be used for and for that reason have the nice touches that make the difference. As I'm always taking different gear to different events I end up swapping things around and these bags have so far proved reliable and durable.