It is interesting that both the Beach Boys and Four Seasons influenced each other. For example, “Rag Doll” has a similar style to “Don’t Worry Baby”, and “Finder Keepers Loser Weepers” sounds like “Big Girls Don’t Cry”; “Sherry” and “Walk Like A Man” also have the Beach Boys style.

Both groups also influenced other bands, such as the Beatles, the Hollies, Jan and Dean, the Ivy League, and the Rockin’ Berries.

Both bands are great, and definitely earn a respectable place in rock and roll history.

http://www.ripchords.info/

Growing up in SoCal, surrounded by if not immersed in the beach and car culture, I would say that the 4S had an edge in popularity pre-Beatle, but after the Invasion, that edge flip-flopped like a 45 loading in a jukebox. Everybody dug the BBs but the 4S probably had a few fewer big fans.

A few more random thoughts re all of the above:
I never considered Bruce Johnston a real BB.
I have often told my sons Mike Love is one of the luckiest guys in rock’n'roll – because his voice is average at best, and often a bit nasal. Brian’s is a thousand times better.
That being said, imho nobody touches the BB’s harmonies at their best. Not the Beatles, the 4S, the Mamas and the Papas, Queen, or whomever else you’d want to insert here. Magical. Even if they had to do a hundred takes.
La Jolla is also mentioned in Surfin’ USA. And didn’t Rick Elice describe Christian Hoff in early interviews as a blond SoCal surfer boy?

Adrian Baker, who is the only touring member I know of who was with both The Four Seasons and The Beach Boys, sang “Sherry” at Beach Boys concerts! Right in front of Bruce Johnston! But Gidea Park, a group that does imitations of both groups, and used to have Adrian Baker, sounds much better in the recording studio than it does live.