Actually pretty good
For the most part, the actors did a good job of capturing the essence of their comic book counterparts. And aside from the take it or leave it plots involving Pop's eviction/Mr. Lodge's excessive greed, it's an entertaining, feel-good look back at characters that a lot of us grew up with. It's a little saccharine at times, but then again, so were the comics. And the way that it ended was just great!
If you like Archie comics, and can accept that the premise of this movie removes the characters from the high school context, then I think you'll enjoy this!