I've got a 4 year old Tomtom, and a 1 year old car with a Garmin jobbie semi-built in. The Tomtom is much, much handier to use, more intuitive and generally more practical-use friendly. In my experience with a variety of Garmin non-car GPS devices over the years, they make nice devices, but use utterly crap software to manage them. The one built into my car runs Windows CE
As for having any satnav without map updates, I reckon thats just plain silly. Either get one with lifetime updates, or subscribe, and connect the thing to your PC or whatwever, regularly for all the updates, including the little GPS updates that Tomtom gives you that they sauy improve accuracy (dunno how).
Yes, you can navigate with a smartphone, but a car satnav is optimised for use in a moving car, they just seem so much more usable. That said, I've just got a bracket to hang my expensive smartphone on the bike handlebars to use for nav, so I'll see how I get on with that. I've removed the Etrex bracket, as compared to modern devices, that thing is so user-unfriendly unless you are walking.