Octalink ES25 replacement?

The BB on my MTB makes a ticking sound when warmed up, sounds similar to
a hot car engine after it is turned off. It has also develoved an ever
so slight play, just a few mils. It is an Shimano ES25 Octalink.

How long do you guys let that go before replacing?

Can anyone recommend a better quality BB for this that lasts longer than
5k miles and doesn't cost an arm and a leg?

--
Regards, Joerg

http://www.analogconsultants.com/