As a loving wife

Yeah, I really wouldn't pay much attention to those who offer advice but warn that hubby is going to eventually suck cock or give away his ass. I too would enjoy seeing my wife have sex with another man. I'd prefer that man be quite a bit more endowed than me (~ 10 inches) so I can witness the reaction of my wife who has never felt something that impressive in her before. But I have no urge to suck the bull off or to be fucked myself, and I reckon your hubby feels the same. There are all types on CS. Your hubby is likely more of a ... who derives sexual pleasure from watching his wife take another lover. It satisfies something primal in him and turns him on immensely. If you truly love him then you should at least contemplate it. He is likely coming from a sincere, safe place and believes it would be beneficial to all those involved, especially you!