which logo is better?  

They are two extremes that are missing something of the other...
The KFC logo has all the desirable qualities of a logo arrived at through a lot of focus group revisions. Its bold. It communicates instantly what it is. It has some feel good. But it is so simple and direct it reminds me of southern fried Soviet poster art of the 20s-30s. There's just something totalitarian about it. Maybe that's appropriate for an outfit that kills millions of chickens raised Matrix like chicken farms and slaughtered for their protein.
On the other hand, Harold's just doesn't hang together and it would easily be lost in the image warfare commonly experienced in strip mall America. It needs some kind of organizing visual theme.
You might wish you'd eaten at Harold's, had you seen it, but what you saw was KFC and you were hungry, so you ate there.
And I'm someone who generally prefers wacky, vernacular signs like Harolds. I mean Harold has a great central immage...a cook chasing a chicken with a meat clever...that comes out "fresh" no matter how many times you see it. But its kind of reduced in impact by the related and unrelated clutter on the sign.