I absolutely will NOT deal with anyone who demands F&F.
Same here. And no exceptions.
On another audio website, I inquired from the site's official vacuum tube vendor about the purchase of some tubes. When I asked for payment info, he requested PP F&F. I declined.
The vendor then contacted the site's administrator and accused me of backing out of a deal. He also claimed harm because he'd already special ordered the tubes for me. That only confirmed my suspicions about the guy. (These were common tubes: 6H30 and 6550.)
Any vendor that seeks PP F&F can't be trusted, imo.