I love Izumi chains. Good ones start around 20 bucks and up and they seem to last a fair amount of time. Also like HKK Vertex chains as well, but now you're really paying good money.
However I figure if I'm going to put my life in the hands of my drivetrain then a little extra cash is well worth it.
Sadly, I've realised that I'm a sucker for anything thats NJS.