If I had to pick one album only as Van Halen's best, I would choose this one. This is the band at its most ambitious, with something of a harder, darker edge than they showed at any other point before or after. Unfortunately it didn't sell as well as their other records so they got cold feet and did a total 180 with Diver Down, which is a good, fun record but clearly nowhere near as adventurous as this one. "Unchained" is my favorite Van Halen song.
Everybody who says it's underrated has a point, but this is personally my least favourite of all the 1978-1984 albums - rag on me if ya want, but I like Van Halen when they're fun. And this ain't much fun.
Underrated? I've never heard anyone say this album sucks in any way. I think people might mean under appreciated. The term under-rated is overused. Sorry to vent about that here...this album rocks - probably my favorite by VH.