I need to buy a new Garmin but cant decide between the 510 and the 810.
I need it to heart rate, cadence, Strava, speed and all the usuals but dont know which to go for.
I also need to use it on the MTB, CX and the road bike. What would you chaps recommend? What are the benefits of the 810, the chunkiness of it puts me off to be honest… 😳

500 if no mapping requird. 810 otherwise. The 510 offers very little over the 500 except a larger form factor and a touch screen. I use a 200 off road and it is very good (better than the 500 in fact) but will not collect external sensor data.

If you don’t want the maps, then the 510 (or 500).

If you can wait till you get home to upload the route, then the 500. Ok, 510 does have a bigger screen and a few other benefits.

510 also offers wireless connectivity that the 500 doesn’t. Obviously the 810 has wireless gubbins too.

Basically though, as above, 810 for proper maps and navigation, 510 if not

Just seen the post above and curious, why do you find the 200 better than the 500?

Dunno why anyone would find the 200 better. I had two (replaced the first under warranty) and they were both incredibly shit. Plus you can’t actually get your position of it should you need to

Ease of use, clarity of display, speed of GPS acquisition. It is a nice bike computer that additionaly records route and can show a simple course – as per the 500. Even the icons on the case makes reading the buttons much easier – so I swapped the case over to my 500.

I’ve got a edge 200 and it is crap. Not very accurate, only takes gps readings every few seconds so not great on tight/twisty stuff and I’m on my 2nd one within a year.

You can use both a 200 and 500 to navigate. It’s possible to upload tracks and follow them. It doesn’t give turn directions just a route. It’s basic and works best on road or more simple tracks ok.

But as above, if it’s mainly as a training aide I would go for the 500 if you want more detailed navigation it’s more 800 territory.