I'm a big Sammy Hagar Fan, I love his solo stuff (Apart from F.U.C.T. and Balance, I don't fancy the Van Hagar stuff that much)
Being also a VH Fan, we get the same "problem" as with Sabbath. The so called Lead Singer Disease.
The Similarities are just astonishing: Ozzy/D.L.R = great preformers, weak singer, very popular
Dio/Hagar: better singers than preformers, not as popular....
Before I bash anyone: I am on the Hagar/Dio camp, but do like the other eras of both bands. Personally I think the early VH/DLR stuff you mentioned, is underrated. Like "2", "Fair Warning" and "Woman +children first". Evrybody's just talking about "Jump", as with "Paranoid". They're most popular songs and not really a representation of their respective legacy.