Stand alone GPS is my favorite and Garmin is by far the best. Long time ago I had Magellan, which wasn't bad but it's no match to Garmin. What I like about the Garmin that you can have a lot of tweaks and customization's.
If you take your time, you can buy very cheap on ebay.
Also any phone software no match to Garmin GPS. With Garmin you have strong mount on the dash, steady power, satellite, traffic, speed and red light camera alert.
I heard that Garmin sales are down because mobile phone competition, but I don't plan to ditch it any time soon.
Smoothpainte