How do tell when my stylus is too much worn?


I have had my MC cartridge for about 5 years. I haven't kept a proper log but I would guess about 7-800 hrs. How can I tell BY LISTENING that it is worn enough to replace or retip? Does it get edgy or shrill or....?
I suspect that the change would be so gradual that it might be hard to tell, as the ear slowly accomodates.
Of course I should remove the cartridge and view under a microscope but un mounting and remounting is a perilous business that I would like to avoid.


rrm
I keep my cartridges very clean. They last a lot longer than they probably should when reading about what manufacturers/reviewers say cartridge life is. In my experience the suspension starts to go bad. When that happens things start to get muddy. 
I always use a test record when I install a new cartridge, and use it as a reference to check the cartridge.

I can buy a big telescope and pretend to be astronomer but the

telescope as such can't make astronomer from me. Well by

comparison with whatever miscroscope ...Consider all those

styli shapes. After loking at, say, 3 kinds one can't remember

either except the old ''trusted'' oval kind.

So the answer depends from our belief. Belief in the honesty of

our retipper as well in his capability to judge the gradations

of wear . The problem is that they can charge 500 euro for a

simple retip by which the cantilever/stylus combo is glued on

the tube rest of the old cantilever. According to Andreoli who

learned the trade by Aussie brothers he was able to do this job

in 5 minute time.

Fermi has stated: ''If I was smarter I could remember more of

those particles than I actually do''.