I went thru four Zumo 450's and three 376C's. They aren't hardened enough for real dirt riding and I was using the damped Touratech mounts too.
If a Garmin product is dead it's because they know the real numbers for all the failed units and they killed it to save their reputation.
Be sure the safest rule is that we should not dare to live in any scene in which we dare not die. ~Lewis Carroll~