I've had a few bad experiences with master links. Perhaps we don't know how to properly apply them. They've dropped the retaining clip from time to time but we've never actually lost a chain due to a link. Anyway, I've gone to using a pin extractor re-insertion tool like on the bottom of this page
http://www.tmkartsupply.com/index.php?page=chainek
I had to file the pin straight ( it started to bend from uneven contact) but now it works like a charm and I don't have to worry about finding a good master link or loosing the parts of the link when I'm in a hurry.
The trick here is that we've come up with a design to allow us to make a continuous loop chain that can be easily removed and tensioned. So we make the loops and never have to break the chain again. It took a little practice, but I'm satisfied the link is as strong as the original chain.
Steve
We've never lost a chain but had the retainer and the outer side drop off and I'd rather not deal with that. I think the trick is being able to snap that clip on with JUST enough force. Maybe needle nose pliers are not the right tool.
Steve