Having spent a few weeks emailing a Tesla sales member about the options for my Model X order, I thought I'd share what I learned here for others. Some of this may be "obvious" or already confirmed elsewhere. 1) Unlike the Model S, the base model of the Model X has a NON-leather steering wheel. (The sales team member initially got this wrong and I had to question more to get the correct info.) 2) The steering wheel is upgraded to leather by purchasing EITHER the Premium Upgrades Package with leather seating OR the Subzero Weather Package. 3) The Ultra White seats are "a synthetic material". 4) Like the Model S, you may special-order a vegan steering wheel, and it results in losing the heated steering wheel feature of the Subzero Weather Package. 5) The second-row seats do not fold, they only lean forward. 6) None of the seats are removable by the end user.