You can't go wrong with the Garmin Zumo 550. Vibration and waterproof. I have logged about 13,000 miles on mine with no issues. Easy to read in bright sunight, you can load thousands of songs on it, and if you want to pay for the subscription it has XM radio. It wires directy to the battery easily. Bluetooth compatabe. Comes with everything you need right out of the box. I have also dropped this unit 3 times !! with no apparent damage. To me it was worth every penny...I was in Ontario's far north last year, and the Zumo found me a gas station out in the midde of nowhere.
Steve