I'm a Blues purist and my favorite blues band is Peter Green's Fleetwood Mac with Jeremy Spencer on slide guitar. Just listen to the 1st album. So when 1975 came around I was disappointed with The Mac for there new sound. I thought by adding Christine McVeigh (Perfect) on vocals the blues thing would continue. Check out Christine on any 'Sugar Shack' Album  she was great. But over time I did enjoy the band for what they became. What I didn't like was how they stopped what got them  them on the map to start with. GPN has had some comercial success but at no point have they stopped playing the 'Jam Band' stuff that peaked my interest to start with. I even enjoy the comercial things because the song writing and playing is still great and when I see it live  it still brings me to 'Tears of Joy'.