I would say that Garmin (in general) are most stable and reliable navigation devices if you compare them with some none branded cheap shi*t devices from China or even with many other known brands. In my opinion it's also most user friendly brand comparing to Mio, Tomtom etc., regarding map updates and navigation algorithm. Also, I never saw any garmin "crashing" or throwing errors. But nevertheless it's an electronic device and none of them is immune to various malfunctions or glitches which can occur. I have tons of experiences many of them so I think Garmin in price range as it's Drivesmart 55 could be ranked into best buy devices/series regarding price/performance/quality. But that's just my opinion, some may not agree with me from different reasons.
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