I love Hagar's voice. It's sort of bluesy and fits the more pop-ish sound nicely. I also like how keyboards are used, but not to the point of depleting all the rocking qualities. It's still hard rock, just more accessible. The fact that the bass is downplayed annoys me (seriously, that's a big deal imo), but that's not enough to detract from the whole experience. Van Hagar is quite good, just different. Different in sound and songwriting, whether it's for better or for worse.
That said, I still have to side with Roth.