Well my stupid motherboard sets 1.4v stock volts with 1.575 spikes under XFR and the chip hasn't died after 10 months... BUT... I did recently reduce the negative offset from I think -0.056 to -0.048, and upped the SoC by about 0.05 to 1.12 ish, which seems to have stopped some bluescreens that had been sneaking in. Three weeks without a reboot so far, probably solid now.
Anecdotally I am not quite convinced that XFR is healthy for Ryzen in the long term. AMD always said it's fine, but I guess we're at the point where we'll start to get user reports if there's a problem there.
Completely unconnected, I've flipped my coat and gone 8700K because Ryzen 2000 just doesn't offer the single thread performance that nearly everything I do is begging for. Which sounds terrible, but actually I'm really glad that there's a 6-core upgrade option (which surely would not have existed without Ryzen), and that in 12-18 months I will probably get an upgrade again with Ryzen 3000. Competition works and I love it. It's expensive, but I love it. I miss the days of annual upgrades and hope they're coming back