BDog, lemme tell ya a little secret:
The problem with fantasies is just that they are that: FANTASY. My personal observation, nine times out of ten the reality isn't HALF as thrilling as the concept.
Now, bear in mind I'm saying the following lightly, not judgementally or critically: If y'all wanna swing, go swing, but don't justify it by saying, "my penis is too small and I prematurely ejaculate so let's have sex with someone else so MY WIFE CAN HAVE A BETTER ORGASM." No, you wanna swing because you wanna swing so just swing, but keep the thought in mind, just like having children, it doesn't fix a bad marriage and it usually makes a fragile one even more insecure (not speaking from experience, it just stands to reason).
But bigger dicks that last forever are called DILDOs. Ain't NO natural man can compete with the miracles of modern technology.
And finally, no, my husband would NOT be turned on by watching me with another person, male or female. Like most couples, we've had this discussion, the final concensus: the "creep me out" potential is too high on both sides. It would just be too damn weird to be a turn on.