What you're talking about is referred to as a "sole guard" which could be called "topy" or "vibram". More info here
I've had a pair topied by Gemmells. They do a good job.
It doesn't wear through quickly. Lasts at least a year usually.
it does sorta change the feel of the shoe in that the leather sole doesn't come in direct contact with the pavement.
you can even get them in a colour that somewhat matches that of the sole:
"Taps" are different, they are placed just on the toe or heel, and can be rubber or metal.
sunken rubber toe tap:
rubber sole guard and sunken metal toe tap:
A leather sole is still something I'll prefer, even though it means they wear down a bit quicker.