Since Daisuki is not available in Japan, I had to watch OPM at hotel TV. It was an adventure all in itself: even had to set up an alarm clock. Screencapping was compromised. But regardless, it's good and I think we can open its run safely.
I remember that back in the day, good old Aroduc was bringing up the quality of fights as a standalone measure of anime (in e.g. J2). I thought gaming made his brain to malfunction. Ditto Evirus and his focus on "mahou shoujo beatdowns" in Precure. But in One Punch Man the fights are amazing enough to matter. The way they vary the animation is quite nice too (although I'm sure not everyone can understand).
Even without that, I'd watch it for OP and ED.
Finally, the characters ought to be quite decent. The anime follows the reboted manga closely.
P.S. A few people found the comedy to stand out. I agree, it's pretty good, but perhaps "solid" is a better assessement.