the only way you will have to take it to the dealer is if you have the active steering option. As for the lowering you should be good. I'm running -1.05 upfront and im not lowered and doing fine wear and handling wise. As far as the rear you are allowed -1.75. I would let the car settle for a few and then take it to the alignment shop. I did mine at pep boys with no issues and also took it to a tuner shop also. No difference only in price.
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