Plug wires for how long?

[Myke456@aol.com]

Does anyone have any thoughts or evidence indicating when/if to replace
ignition wires on a daily driver 5kTQ approaching 200k miles.

 There seems to be 2 rules of thumb:

1) Don't fix what ain't broke-wait until there's a problem. (I have a
mechanic that actually practices this!!!)
2) Replace at "suggested" milage (especially American cars)

It would seem to me that(excluding any external damage to the insulation)the
time to replace, would be when there's an increase in measurable resistance
in the wire.

Thanks
Mike Aiello