Hi: Just joined the Forum after finding some of the posts useful.
I bought a Rand McNally 7710 a week ago in Camping World, St Augustine and used it on the way north to Nova Scotia. I'm very pleased with it. I've seen many negative comments but when you analyze them they are mostly the result of failure to understand what GPS's do. They are not a substitute for brains and paper maps. It worked flawlessly but it does require setting intermediate points if you want 'your' route rather than hers. The screen is a bit hard to see in bright sunlight but the mount works well and adjusted to give the best compromise. The sucker never fell of the dashboard.
When we chose 'our' route to the endpoint, Hilda (what do you call yours?) caught on quickly and recalculated within a few seconds.
One difficulty is the computer generated female voice which can really mangle many words. It would be good to have a wider choice of 'people.' Male voices are no good for Hilda - She who must be obeyed - can only be female! One thing I didn't like was being told to "slide right in 200 yards" or whatever. Often the sliding wasn't required. Sliding is a term with which I am unfamiliar!
A major failing, which some think is a problem with the GPS are inaccurate lat/longs for campgrounds. Two of ours were spot on while others were wrong by a few miles. I'm not sure how lat/long info is obtained. Is it worked out from street address or do CG owners enter the info into a database? Street address entry always worked accurately. Certainly the 7710 isn't responsible and I'm not sure if Rand is either.
Speed limits were usually quite accurate but on several occasions had not been updated to reflect changed signage. I don't know whether Rand is better or worse than other manufacturers in this. I was running the latest updates.
The 'manual' is sketchy but the unit was almost completely intuitive provided one remembers that it is merely a computer and requires logic. My wife who is computer literate learned how to make it work within minutes. I'm not the navigator.
I was disappointed that the traffic info doesn't work yet. Other manufacturers already have this. This is a real nuisance on the I95 where one spends a lot of time recalculating and finding parallel roads!
The Dock software could be more useful. I haven't found out if it automatically starts if I connect the GPS. I expected an icon on the desktop. It seems merely to be a downloader.
I can't provide any comparison to other manufacturers but I imagine all have good points and bad. The Rand certainly picks up satellites very fast, much faster than my Llowrance handheld.
I look forward to finding out some hints and tips from users.
So here is my brief assessment for what it is worth. The bottom line is that I thought the features in the Rand were more useful than in other manufacturers. You pays your money and takes your choice.
Donald