I play 80s glam/thrash , wondering which would be better for me in a half stack?
I don't have much experience with the valve king, but I own the windsor, and as such, I can tell you that it sounds great for distortion, and has a lot of gain on tap, but if you'll ever need a clean sound, the windsor's not for you, since it's basically nonexistent on this amp. If the lack of clean doesn't bother you though, the windsor is a great amp at an even better price.
Valveking can handle it fine... Especially with a tube change... The JJ's i put in mine give my amp a really nice Thrash tone now.