I am moving to the 510 after 4 years of using a 500. I've been using it for only a few weeks, but some immediate impressions: living in NYC, one of the minor but real annoyances is waiting for satellite capture. The added GLONASS really makes this almost a non-issue. No more waiting 5-10 minutes or losing out part of the ride from no satellite link. Otherwise, it does the basic functions of the 500 just as well; still getting used to the swipe screen (one of the reasons I had to get a new device was because the buttons on the 500 were getting harder to push as they disappeared into the casing). I don't use the bluetooth function to upload rides, but I did it once and it worked. A second try didn't capture the phone. User error? My main concern for the future is battery life; I have some long rides planned, 10-14 hours, so will see if it manages. The labelling of ride "types" is not useful for me and gets in the way but is ignorable pretty much. All in all, just for the satellite capture, this made it worth the cost over the 500.
My first Garmin product and I am loving it! It packs so many features for riders and customize settings for different bikes is easy.
I like the customizable display very much , many functions and high c/p ratio. You dont want to try another brand after you tried it.
A great product with every bit of information needed. Bluetooth upload is great. My only issue is I have to find and sync my cadence sensor Every time I've used it so far