We have the Good Sam Rand RVND 7725 and have found it to be very reliable and accurate. I use the GS Trip Routing Program on their website. Once I've got the route laid out, I can download it into the 7725.
All that being said, I also use the built in Jensen GPS and compare both. No discrepancy, we're good to go. If there is a discrepancy, out comes the paper trucker's atlas...to date, the 7725 has only been wrong once and that error was in taking us on a "shortcut" that was an OK route, but, that route bypassed a Pilot station I wanted to use. Turns out it was my mistake...I didn't download the "final" (all changes made) version. The moral of that tale is that no matter which one you choose, you can't "bet the farm" on its accuracy; that's why we use 2 and let the truckers atlas settle any discrepancies.
Don and Bronwyn
Down to 1 cat now; J-Lo
2014 Tuscany 40RX
2015 Jeep Cherokee Trailhawk towed