Your Garmin help, please

I had the same problem with my 800, they tend to freeze after recording a certain amount of information in one go without resetting apparently. Pain in the arse!

The thing is I have recorded a 300km audax with it before, but I manually paused it, then forgot to restart it for 25 miles or so, so it only recorded 176 miles of the ride.

This certainly would explain what happened.

So, Garmin 200 is the one to get if I only need the occasional bit of directing?

Yep. You won't have maps, but you can follow the line and apparently it is very clear where to go. It will also take TCX files, where you get a little arrow at each turn, but you won't get turn by turn navigation which the 800 will do (e.g. mine will say 'Turn right down Letsby Avenue' as well as have a big super clear arrow overlaid on an OS map).

Thing is this is nice to have but not essential. I want reliability and decent battery life more than I want that.

I've not had problems with rides under 150 miles though so I guess this is a niche problem.