I resisted getting a Garmin for a very long time. (In spite of the fact that I often get bonus miles on brevets.) I really don't care about the data tracking, I don't ride with a HRM or power meter. I don't even care too much about speed.
I'm pretty happy at this point riding with an 820. I still ignore most of the data functions, but I am very glad to have the nav functions. I've also found you can extend the battery life by turning off some of the unneeded functions -- I can get 12 hours no problem (200k and 300k). For rides up to 24 hours (400k and 600k) I've had good luck with an Anker external battery pack but this would be a problem on a wet brevet. I don't have any experience with it yet on rides over 24 hours.
I use RideWithGPS (RWG) and upgraded my account to get turn-by-turn notifications. I typically increase the notification from 30 meters prior to each turn to 40 or 45 meters. I also have a "Distance to Next" field at the top of each screen on my "Brevet" profile. This, plus the beeping, means I no longer miss a turn because I'm lost in thought, worried about other riders, or watching traffic.
I've also found some really cool rides in my area by browsing RWG and I'm looking forward to finding routes when I travel this summer. I also like the route planning function in RWG to find new rides of specific distances and/or difficulty (like elevation profiles).
By the way, thanks to all you early adopters for working out (most of) the bugs before I joined in!
PS - I still make sure I get a printed cue sheet for every brevet.
Last edited by Flamme Rouge; 02-22-17 at 01:36 PM.