Welcome. I don't believe you could go wrong with either and heck why not have both. Give the used zl1 market a few months and pick one up avoiding the instant depreciation of a new car. When the gen 6 model comes out make a decision on the switch based off performance and features without an immediate loss of investment if you choose to do so; if a loss occurs doing so will be nominal
Have that cake, eat that cake and throw that sh1t on anyone who says otherwise.