I have a Legend and the bike mount for it. The current incarnation of the bike mount is OK. Word is that the first version was too loose, and the batteries would vibrate loose if you hit a bump, and the GPS would reset.
The speed and distance are spot on. I mean, how could they not be?
I only used mine a couple of times; I fine-tuned my bike computer with them (it was about 0.2 mi off in 10 miles, so I added the right percentage of mm to the tire circumference).