Moodymann can get away with sampling what he likes because he's got a worldwide fanbase of sycophantic, pot-smoking, students. He also feels he's got the higher ground as he's black and only blacks can sample real soul music.
That said, the cheeky farker sampled the especially white Bob James on a track which sounds as uncool as its title, "Spunky". The result is the Moody one's coolest piece of sampling, ever:
http://www.divshare.com/download/6626456-c53 (listen from around 1:30 and you'll soon here it)
And perhaps, that's what makes sampling credible. It's what you make of it and how left-field the sample is. Phats & Small ("Music For Pushchairs"

and Armand Van Helden ("You Don't Even Know Me"

both used a really obvious sample from Carrie Lucas "Dance With You".
Keeping it rare and clever goes a long way in the credibility battle. No one wants to hear another tired James Brown, Brother's Johnson, Chic, Commodores, Chaka Khan or Cheryl Lynn sample.
My favourite sample that I've recently discovered is Global Communication's "The Way" which samples Dexter Wansell's "The Sweetest Pain". You'd not normally think a signature Wansell soul composition could be turned into a 4am, deep house epic but Middleton was inspired enough to hear the sample and clever enough to stitch two elements of the song together.
Original tune:
http://www.youtube.com/watch?v=PctLKcvYLGk
Sampled into:
http://www.youtube.com/watch?v=kNcHM5zJGt4