Sonic highways is different. The album tries to capture the soul of rock music and manages quite well. For me, the album which for cruising, to relax, not to waiver. Sonic highways is very similar to the last side project "Sound City". Both albums show the direction in which the band has developed in recent years.
Conclusion:
Who can engage it, the album is an unusual, quiet Foo Fighters album on which it in no way lacking in musical genius and soul, which will have great pleasure in it. But who expected an album in which he can come off properly, which is unfortunately very disappointed. Personally, I think it's good, but would have at least wanted a proper rock song.