I did a 100-mile mountain bike race over the weekend with the 830. It was a disaster.

Some of this post is me venting but also to bring continued attention for the folks at Garmin to the litany of issues that continue to plague this device.

TL;DR:  This device is unreliable for mountain biking, particularly in a race situation where basic reliability is paramount.

First issue:  My 830 completely locked up somewhere around mile 50.  Not sure how long it was frozen, but looking at the timing results, there is a difference of about 14 minutes between my official time and what the Garmin showed.  I absolutely needed to see my stats (HR, distance, navigation, etc.) in order to execute this race.  The only way to get it back was to hold the power button for about 30 seconds -- which I had to do on the fly DURING A RACE.  Eventually it booted back up, took about 5 minutes to reacquire satellites (why so long?), and I reloaded the course.  This was detrimental to my race performance.  (I had previously posted about this issue here.  Clearly I'm not the only one.)

Second issue:  The touchscreen is unresponsive with sweaty, dirty fingers.  This was a huge issue.  I wanted to be able to quickly switch from the map to a data screen and back.  It rarely worked.  At one point it was stuck on the text message notifications screen (no idea how it got on that screen) and no matter how many times swiped in any direction, I couldn't get the screen to change.  I even stopped riding to carefully try to clean it and swipe.  I had to ride for several miles to the next aid station to get a clean paper towel and wipe the screen clean before it would work again.  This problem existed both with the screen locked and unlocked (by pushing the side button).  I'm not sure if mine is defective, or if it just doesn't work when the screen gets covered in moisture.  I am starting to wonder if I shouldn't have bought the 830 and instead opted for the 530.

Third issue:  Navigation is a joke.  I had preloaded the race course to follow along and know when turns were coming.  At times it would show "0 ft" for extended periods.  At one point it showed "0.3 mi" with a left turn arrow for at least five miles.  I kept waiting for that turn that never came.  

Long story short, this thing causes more problems than it's worth and should not be relied upon in a competitive event. 

Garmin:  When are we going to have a reliable device?