Can you plug a guitar directly into the A6, like with the SP?

I was wondering wheteher it was possible for a guitar to go directly through the A6 like one is able to with the SP808?
What effects do you miss out on with the A6?
Does the A6 still have Mic simulation, or amp simulation?
What advantages are there to owning a SP instead of an A6?

Thanks for any information
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