I have HW:B1, with 2.02NA firmware.
I've only had mine about 1.5 weeks, but once I got it configured, it has stayed-up just fine. I let it run about a week, then shutdown for an incoming thunderstorm.
"DNS Relay" is disabled. I never had it "crash" the router, but the router is too small for a reasonable DNS cache so after I understood what it was, I disabled it.