I think 5FDP's first album, Way of the Fist, wasn't exactly a breath of fresh air for metal, but I think it was something new. I really like that album. One of my favorites in the past five years. It has some very heavy songs like Way of the Fist, White Knuckles, and Salvation. Their second album had some great songs like Dying Breed, Burn it Down, and War is the Answer but a lot of cheesy radio ballads. Their new album has a few memorable moments but a lot of cheesy radio stuff again.
I think you can consider their new album radio rock but don't label them as a radio rock band. When I think of radio rock I think of shit bands like Theory of a Deadman (worst live band I've ever seen), Seether, Three Days Grace, and Alter Bridge. Those bands just rely on one or two solid singles with shitty verses and catchy choruses to be popular. Show me one song either of those 4 radio rock bands made that is like Burn it Down, Way of the Fist, or White Knuckles.
I saw 5FDP at the first Mayhem show when they were on the side stage. It was in the top 2 most brutal shows I've been at. I had first row against the barracades and I broke a rib. They had the place going nuts. White Knuckles was one of the most insane live songs I've ever seen. I then saw them at Mayhem two years ago when they were on the main stage. The crowd was a lot less aggressive and they had way more fans. It just shows how they've become more of a radio friendly band, but at their core they still are very heavy.