It all depends on what you want to play on your guitar (Rythem/Solo/Fingerstyle)
Personaly for me its 1 7/8' V neck for fingerstyle, 1 11/16' for Rythem & Solo...
I didnt find in my area a 1 7/8' inch guitar so i bought a 12 string Washburn guitar that had 1 7/8' and turned it to a 6 string, very happy with it although i know that once i do find a 6 string with a V neck and 1 7/8' ill replace it, if someday i have enough cash a custom built or a Martin Ditson 333...IF i find a Martin HD28VS (1 3/4' with a V neck) that might do aswell
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