I purchased a few years ago a Garmin GPS for my car.
The GPS was sold with free lifetime maps updates.
When I connect the GPS to my computer and ask to do an update, the GPS stays a while Online and finish with a screen "Your GPS has already the latest update.
But I switch the GPS on, a lot of streets/roads are missing and a lot of places are wrong or completely missing.
I tried to ask Garmin helpline about this, the HelpLine seems to be missing too and fails to answer.

 

My question is, are there other GPS manufacturers who have the latest updated maps and are compatible with Garmin?

Google seems to have the best maps, but I don't know if Google maps are compatible with Garmin.

I spent 4000 baht at Panthip plaza to buy the Garmin GPS for my car, soon realized it's useless and doesn't have updated roads, particularly in areas where there have been modifications/ diversions. Plus of course, it doesn't give real time traffic data. Much better to use Google maps on your phone (better Android, although now you can get on iphone too), and stick the phone into one of those thingummies on your windscreen. Works for me driving all over Thailand. 

I was told that there are black market versions of updated Garmin maps. How that works I don't  know. 

I do miss my old Tomtom GPS that I had back home but for me it has to be Google maps, works on any phone, followed by Sygic which will also get you there, sending you however on the same route whatever the traffic is like. 

 

 

I use the TomTom Go app on my Android phone. For under 1,500B for three years it provides me with (more or less) global maps that are updated every few weeks. I also get live traffic data via the mobile phone signal.

 

I see no future at all for individual satnav devices.