Originally Posted by gpelpel

I just got one, was using the Edge 305 before.
I like the smaller size, the bike mount has been improved a lot (no clip to break, no accidental unclipping) and the battery runtime is close to double.
Some complain that the screen is more difficult to read due to glare, I find this true without glasses but find it a lot more readable with my polarized glasses. So if you don't wear glasses or don't have polarized lenses you might have to invest into a cheap anti-glare screen easily found at office supplies stores. On the other hand if you have polarized lenses you will love the improvement.
The Garmin software still suck so make sure that the third party software you are planning to use support the 500 .fit file format. I am a Mac user and love the Ascent program from Montebello Software. Ascent has just been upgraded to support the Edge 500 thus my very recent purchase of the unit.
When connected to your computer the 500 mounts as an external drive making it easy to drop files into it. The drawback is that you have to wait a little bit for the unit to mount before being able to synch your activities, it takes about 35 seconds on my computer.
Some nice additions are the ability to scroll through up to three screens automatically (you have the option between three scrolling speeds), more data type choices (HR Zone, Heading...), temperature, and ant+ compatibility with power meters.
I think it has been well thought out and offers pretty much all what most riders need aside from mapping.