Regarding firmware updates: none of the changelogs make any mention of fixing this, so I'm assuming it's not fixed. I'm not prepared to try; I always re-set the tracklog at 200k or 300k. I'd not let it go much over 300k before re-setting it.
Just my two pennies: I got an 800 last year a week before the 810 was launched
(However, being a techie I wouldn't have bought the first version of the 810, because it's bound to be buggy and/or feature limited, and it was.)
Anyway, I have had only a single software crash that I can recall on the 800 in 15 months/7000km and I don't recall losing any ride data. I used it successfully over four and a half days of LEL last year – I generated a single FIT file with the entire ride data in it (barring a little bit towards the end where I connected it to a laptop to check the route – connecting to a computer saves the recorded tracklog and resets the unit, whereas switching off for sleeping and back on again doesn't, although you have to remember to hit Start in the morning before setting off!). So LEL was 1300km in a single file (and 120km in a second one). I've done four 600s, two 400s and numerous 200s and 300s without any logging issues (except the last 600 failed to report calories estimate for some reason, perhaps HRM wasn't consistent enough?).
However, there are three particular issues that I wish they'd fix:
1) When using the 800 for turn-by-turn, somewhere beyond 350-400km then the unit STOPS giving turn-by-turn instructions and you have to stop the Course (NOT the tracklog, just the Course) and start it again and it commences with instructions. The problem is that you have to notice it has stopped doing it in order to fix it, by which point you will have passed your turn (I have a data screen visible, not the map display, so I wouldn't know this unless I also had a routesheet, which I usually do anyway). Splitting very long rides into multiple 200-300km legs works well. This DOESN'T affect the tracklog, which will continue recording happily in the background when you change Courses.
2) Even with a specific track set up in RWGPS and downloaded as a TCX file, the 800 will occasionally re-route in entirely the wrong direction on the road, usually at night, and you have to restart the Course (again NOT the tracklog) to get it back on route. It wanted me to turn right at a roundabout the other day when the pre-programmed route AND the clearly quickest route went straight on. Again, having a routesheet mitigates against this.
3) At none-priority crossroads (where you don't have priority and have to give way) and eff SO @ LH/RH bend, i.e. where you are crossing or changing the priority but not actually changing direction by much, there is no turn instruction given. So at crossroads you have to follow your nose, and if you follow the bend around then you immediately get a Course Lost warning and have to double back. AGAIN having a routesheet mitigates against this. What's annoying is that often it will say "carry straight on" when passing a T junction but doesn't say that when at a cross roads or turning off the major road on a bend.
It seems you can't trust the 800 to guide you properly unless you follow the track on the map view. However, its connection to HRM and cadence sensors means you get much more real-time data on the data screens, and I find that really useful, so I persevere with its foibles and continue to use a traditional routesheet as well.
My 800 is on software version 2.40: I can see there's a later 2.70 release, but nothing in the notes relates to me, as I don't use VIRB (whatever that is), or a power meter. However, I'll update and give it a go.
