I have a TomTom XL Europe Traffic, which is my third TomTom. Where I live, TomTom has by far the best maps so there's not much choice. (Last I checked, the Garmin only had main city maps for Eastern Europe).
One thing I really like about my latest TomTom is that the suction-cup mount is integrated into the unit, and the suction cup can be "screwed" on to generate suction so it doesn't fall off. (Here's a photo I found:
https://www.expansys.com/zoompic.asp...=item&i=167772 )
This is a big improvement over previous TomTom models for 2 reasons:
1. The suction mount never falls off since you "screw" it to the windshield. (You then "unscrew" it to remove it)
2. Because the mount folds easily onto the unit, it's easy to remove the unit and the suction mount and take it with you (or hide it) so there's no signs you car has a GPS in it. Just leaving the suction mount (without the unit) on the windshield can attract thieves, as I found out the hard way with a mount on my other car
I can't really comment on whether it's better or worse than other brands at navigation or getting the GPS signal, but probably you can find a lot of reviews online about those details.