Thanks, fellows, for the info. As with so many things, I feel like the last person to learn about this stuff. Anyway, after putting in my address just for introduction, I've discovered both mymap & gmap put in some things that aren't really roads...they're more like driveways and in some instances, roads that don't exist. This could potentially be bad if copied off for use as a cert map.
I'm going to try one of the two sites for my next measuring map...see what happens.
Dang, it just started snowing & it's only Oct 12th!