lp jr's look like their for weenies. esp, les paul, or schecters are going to be your best bet.
My bands lead guitarist uses a Epiphone LP Jr with an X2N in the bridge. It's all black with a black pickguard and it's metal as hell. You play a LP Jr. with an X2N and tell yourself it's not metal. It is metal as hell!
If you play it with a metal style, with a decent pickup and the right amp...
Any guitar can be metal.

Case in point: http://www.youtube.com/watch?v=BzgV8xLOhR8
Epiphone Les Paul goldtop (EMG 81/85)
Epiphone Les Paul Custom
Fender Telecaster MIM
Epiphone SG Special
Jay Turser JT200 Serpent (GFS Crunchy Rails/Crunchy Pat)
Dean V-Coustic
Ovation Celebrity
Bugera 333-212
Crate Blue Voodoo 120H
Nah go for something of a different brand, like the Dean MLX, ESP 50 series or the 300 dollar Jacksons. If you want cheap metal guitars.