When it comes to swallowing versus spitting ladies... just consider this. Let's say your guy has gone down on you and it's time for "the real thing". Which would you prefer?
1) He discretely brushes the sides of his face against the sheets on his way back up to eye level and is ready for more (unless you are still basking...)
2) He jumps-up, runs to the bathroom, starts spitting in the sink while rubbing his mouth with a towel. Then he brushes his teeth and comes running back into the bed.
Spitting is kinda like saying "wow that grossed me out" without saying a word