#1
I have 3 guitars. An Epiphone SG, Ibanez RG, and an Arias Pro II strat remodel. My amps are a Marshal MG 50 and a Roland 20x Cube. I want to know which guitar fits better for Drop D, Drop C#, and Drop C. The music I intend to play is mostly oldschool hardcore/metalcore like 7 Angels 7 Plagues and Poison The Well.
#2
It depends on the scale length really. Lower tunings benefit from longer scale lengths and thicker gauge strings. No guitar is generally "fit for a tuning".

Get each one set up for a tuning of your choice with strings that suit that tuning.
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#3
The RG would keep tension on lower tunings better, but the difference isn't really that big. You can do it with all three with the right strings.
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