Yes you can, I just happen to like Motorhead a lot more.
Progressive Rock to Heavy Metal (Don't get into sub genres because I said Heavy Metal)
You could, however compare Motorhead to:
Anthrax Anvil Bad Company Black Sabbath Cannibal Corpse Alice Cooper Dio Cinderella Exodus Faster Pussycat GWAR Iron Maiden Judas Priest KISS Megadeth Motley Crue Ozzy Osbourne Pantera Poison Quiet Riot Ratt Slayer Whitesnake ...
I'am just messing dude, I wanted to see if you would get butt hurt. Nice list except for the glam bands. Exodus is one of my favorite thrash bands, but Motorhead is still my favorite overall.
I love Megadeth, probably tied with Exodus for favorite thrash band. Rust in Peace and Bonded By Blood are classics. I use to listen to Metallica a lot but not anymore. I still give kil em all or ride the lightning an occasional listen though.
Beethoven - Fur elise Der Ring des Nibelungen- Richard Wagner
I lol'd at how you went from a 3 minute piano piece to a 14 hour operatic cycle. I still can't believe I managed to sit through the whole of Tristan und Isolde when I don't even understand German.
There appears to be no genre limitation, so I'm going to nominate Radiohead and Deftones.