I recall when one of the Gadget mags (GPS I think) put TOMTOM. Magellin and Garmin up head to head to head in 3 sample route jobs
The Garmin won every time. All 3 routes the Garmin user got there first and turned RIGHT into the parking lot. both Tomtom and Magellan brought the driver to a LEFT turn.
(Right turns are safer it seems)
I use the Google Maps on my phone but I will tell you it has issues so I often override with brain.
Example if going from where I park in FairPlay SC to Savannah or Darien GA it will at one point tell me to turn left.. Left is a chain link fence You go Straight (The road you are on bends right but you continue STRAIGHT onto another road)
Likewise I visited Camping world (Former gander mt) store in Flint. it said "Your destination is on the right... No.. Left. but you use your brain then
Still the program was free and usually does a decent job provided I look over the route and make the right choices.