I replaced them with regular foam earplugs and have been just as happy. The metal holder is really
The DownBeats work.  They were semi-uncomfortable at times and warped a little bit after only a week of use.  In their defense - they were being used heavily however, I replaced them with regular foam earplugs and have been just as happy.  The metal holder is really, really nice.  If you absolutely must have your own earplugs and don't like the foam ones I would recommend these.
Rating: 4 stars