I heard different.
SC’s teams on the boys side (Temecula, MV, Elsinore) were/are generally not strong. EA2 was the highest level I believe, and they rarely had a SoCal team place high in league or making deep runs in a tourney. MSA, much stronger on the boys side. Less so girls. I don’t know, but heard, that City is better on girls side.
In that way, it’s a very complimentary acquisition, and it was aimed entirely at adding MLSn in another market beyond Carlsbad. I have no info on cost, but the move took all the line coaches for MSA by surprise is what I heard. I assume it was not a cheap deal. MSA had a lot of teams.