Line 6 are ok... the one's i've played on and heard are too digital, they just don't sound true, neither do their pod 6 toys, and for the cheap one's they have two sounds, clean or distorted. A lot of the music I listen to calls for more dynamics and more amp settings, but for straight ahead metal and rock, line 6 are awesome.
Never heard a Marshall I liked...
Im not a big fan of Solid State. I really like the deeper, rich sound you get from tube amps.
i really like Hughes and Kettner, Hiwatt, Soldano. Big fan of celestion Vintage 30 speakers, greenbacks are alright as well. Not a fan of EMG's, i like Dimarzio over them, Seymore Duncan are ok... Bartolini pickups have a nice fat warm sound.