Just ordered an 820 from these guys as they seem to be the best price I could find online

Slane Cycles

You can even get an extra £5 off by signing up to the newsletter.

Any idea what maps come with it? It mentions a full cycle basemap, but I can’t find any reference to what countries it covers. I’ve got full Europe street level maps on my 800, so I’d want to replicate that.

What are the improvements of the 820 over the 810?

10 of them

£10 cheaper here, not sure if there are any differences?

http://www.rutlandcycling.com/368572/products/garmin-edge-820-explore-gps-computer.aspx?origin=pla&kwd=&currency=GBP&gclid=CLjltu-1k84CFRPjGwodHI4DpQ

‘Explore’ version has less features

As Jamiep said, explorer version has a lot less training features and also doesn’t have Wi-Fi which the ‘Full’ 820 has

I’m split between the Garmin 820 and the Mio 505.

I currently have the Mio 305 which is perfect up to 55 miles, beyond that it seems to be VERY slow to react to screen presses and sometimes crashes mid ride losing all the data – I think with a better processor it’d be a great piece of kit.

Decisions decisions…

Must resist. Nothing wrong with my 810 😕

As far as I can see all the new features on the 820 over the 810 or the 1000 are for roadies e.g. linking up with radars and lights, training programmes, tracking other groups and riders.

If you want to use custom maps, follow an off road trail you’ve created or downloaded, record your route and elevation all the functions are the same. I’d save yourself a load of cash and stick with an 810.

If you’re not a roadie and haven’t had a garmin before you’ll come to realize that once you get past all the gimmicks it’s just a case of charge it up, turn it on, sort your route and map, press go at the start of the ride and stop at the end, upload and repeat.

Must resist. Nothing wrong with my 810

810 recently got us off a mountain, knee deep in snow with no trail to follow and 2m of visibility when we were heading off in the wrong direction towards a cliff face. Off course warning, follow the trail on screen plotted on an OS custom map.

Nothing wrong at all.

820 has a special ‘battery saver mode’ which extends battery life but I have no idea what that means in reality

For me, I had the 800, the bluetooth and Wi-Fi were big plus points, the wi-fi you can just finish a ride and as long as you are in a known wi-fi signal (home, pub etc for example) it will upload the ride details to your Garmin account automatically, no need to connect to PC or phone.

I’ve had my 820 just over a week now, the two bugs/omissions that annoy me at the moment are.
1. Incident Detection keeps turning itself back on, the system works but it’s pretty useless on a CX bike, as soon as you brake hard on rough ground your phone goes off and you have 30 seconds to hit cancel.
2. There appears to be no way of resetting the elevation, with my 810 I press start within 30ft or so of a known pre set point (eg Home or Work) and it resets the elevation to that point. This doesn’t work with the 820.

Apart from that I’m pretty pleased so far.

Nice one OP, was going to order one earlier in the week but couldn’t find anyone discounting. Great price (plus the voucher!)

Don’t forget your Quidco for 3% cashback!!

Good shout on Quidco, I’d forgotten that, mine has already tracked at £8

820 has a special ‘battery saver mode’ which extends battery life but I have no idea what that means in reality

From the user manual:-

Turning On Battery Save Mode
Battery save mode adjusts the settings automatically to extend the battery life for longer rides. During an activity, the screen turns off. You can enable automatic alerts and tap the screen to wake it up. Battery save mode records GPS track points and sensor data less frequently. Speed, distance, and track data accuracy are reduced.
NOTE: History is recorded in battery save mode when the timer is running.