Has anybody had any issues with the GC2/Kwikset 620 combination? Or with their GC2 erasing all their devices?
I cannot speak to the 620 specifically, but it is a known issue (usually seen during power outages) that the GC2 panel Z-wave radio in rare cases loses its device list. The bug is limited to the GC2 panel.
To avoid that issue, a replacement panel of a different model would be needed. I’ve never heard of anyone experiencing that issue four times though, that is an extreme amount of failures.
In general for locks and the GC2, keep in mind that the lock must be learned in within about 6 feet of the panel, then a network rediscovery run after everything is in its final spot.
Locks in particular require this proximity during pairing for 100% success.