Now, in terms of pure price-performance, i think I'd want to buy Ryzen but... this sort of stuff is what scares me off AMD. I just want my crap to work. Reading some of the comments here, one commenter suggested there's an instruction to find an approximate determinant of a matrix where both Intel and AMD are standards compliant but those instructions produce different results on each chip.
Of course I don't know if this is true or not but saving $200 on a PC build is just not something that justifies (to me) dealing with kind of issue or, worse, potentially dealing with issues like these.
I buy NVidia for pretty much the same reason.