If the physical package fits your bars OK I'd bet you will be happy with that.
For training I use a Garmin Forerunner 301 and it is OK for that. For travelling
it can't compare to my old Garmin III+ with it's good antenna. Too bad the III+
won't fit on a truck!

Quick discussion of GPS accuracy: with 3 satellites strong and in view 2 dimension
mapping works and a 4th is required for 3D which provides altitude. I believe
that every vendors software will use more satellites but don't actually know that.
Imagine 3 satellites in a straight line at the zenith which are very close together.
Compare that with three satellites near the horizon as far as possible from one
another (120 degrees apart). The time signals and location from the first three
in a row will be very close together while the three in a triangle will be seperated
more. Any computational errors from the three in a line will be a much larger
proportion of their time differences compared to the big triangle satellite configuration.
Therefore the three in a row will have noticably more error.

Since the GPS system uses LEO (low earth orbit, not geosynchronous ~23,000 miles
away) satellites their congiguration in the sky above you changes all the time, as
does the accuracy. Both of my Garmins have a GPS screen which shows the actual
satellite configuration above you and something which indicates the error magnitude.

A rule of thumb that I've heard is that the altitude error is about 3 times the lat/long
error. I take that on faith but don't really know how it withstands scrutiny.

BTW, I've heard of people who are happy using their GPSs with Google Earth instead
of buying maps. (There may be a $20 US/year charge for the software that integrates
Google Earth with your tracks. I can't remember but I'll bet that Google can.)