I have had a few instances, the only one that REALLY hammered me was a blind smoke sent to me by joeobx. It was going great till just over half way of the cigar. Got the sweats, buzzed feeling, nausea and

after that.
The cigar turned out to be a Olivia Cain, not sure if it was an F or not, but either way, I have managed to stay away from those.