#1
I really like my Epi Thunderhorse, but I've preferred thinner guitar necks ever sense I started playing. I'm considering trading it in for either an Epi Les Paul Custom, or a LTD MH-1000.

Anyone have experience with either of the guitars I mentioned? I'm citing these specifically because I'm pretty sure I could straight up trade for them, otherwise I'd go for one of the new Ibby Destroyers.
LTD EC-1000 VB
Ibanez RG3EXFM1 (Dimarzio Mo' Joe in bridge, PAF Joe in neck, and Sperzels)
KFG Custom
Ibanez RG2550Z Galaxy White
Epiphone Thunderhorse Explorer

Marshall AVT 275
#2
The LTD almost certainly has the skinnier neck of those two. The Epi won't have a baseball bat neck, but it won't be as slender as the LTD.

If you're looking for rock/metal guitars with slender necks, also consider Ibanez and Fernandes guitars.
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#3
What do you mean by "trading it in"? You'd be much, much better off selling on craigslist if you're in the US.
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