MFM really is a lot of fun. I am not in the least bit bi, but I am very visual. Watching Mrs Spoo is incredible - and when the playmate is good, watching her in ecstasy is mind-blowing.
Besides that - I really like to please my wife. Being the center of attention is a fantasy for a lot of women - and the pleasure can be pretty much non-stop; from physical (more hands and body parts) to mental (the power of being able to handle/please two men).
She seems to feel the same about me though - as MFF (and even, lately, the MFFF) happen quite a bit for us, too
One of the great pleasures of swinging is giving - and we just happen to be a very generous couple
Spoomonkey
PS - Our preference, though, if definitely couples.