It's not my first rodeo with pads but changed my fronts and seems put bit too much brake quiet. I think they hardened a bit before i put them in as well. Didn't realize it when I was putting everything together but ended up with pads rubbing a bit. Mpg dropped 20-25% right after the change. Took about 500 miles to clear(didn't want to take everything apart since i diagnosed it)
Moral of the story, be careful how much brake quiet you put on the pads.