Garmin Nuvi 310/760 query

I recently got a Nuvi 310 for my wife which she loves apart from one
feature (so far)

Is there any way of changing the 'time of arrival' at the bottom left
of the screen to a far more practical 'mileage remaining'?

I know you can tap it and then get a screen load of information, but
IMHO it would far more useful to know the remaining mileage to one's
destination on the main map screen.

The ETA is somewhat irrelevant as it depends on the speed, stops,
mileage, etc.

And is this a feature of all Nuvis, as I am considering a 760 for
myself?

TIA,

Richard.

No but it would be nice to be able to put what you want in there, speed,
miles traveled, miles to go, etc.