eeeshhh... Two risers daisy chained like that? IDK if I could do that myself without worrying like crazy. Then again for cards that draw less power, this may be less of an issue.
It never gave me trouble, tried with 3 to test it, worked like a charm, no errors, wires not getting hot.
I'm keeping the cards at 1,2 Vcore max, so they don't get that hot.