(Looks at my CD collection)

Beatles: Abbey Road (and half counts McCartney's Band on the Run)
Stones: Hot Rocks 64-71, Sticky Fingers, Exile on Main Street, Some Girls, Goats Head Soup, It's Only Rock and Roll

Add to TUP's comment about Yoko back-up warblings, Paul let Linda sing too.

Stones by a landslide.
_________________________
$10 says some dude's gonna make a cum shot montage of her to Candle in the Wind - Cum Stains