I am going to apologize in advance if this has been posted or discussed already on here, but I have not been able to find any related talk. Does one have to use premium fuel for the new LX 600? Not sure why Toyota is recommending it as it does add significantly to the travel expense with as many miles as we put on a vehicle in a year's time. We are considering a F Sport trim coming from a Sequoia-my 200 gets regular. Perhaps there is a better mpg on the LX to help negate some of the increased fuel cost of regular vs premium?