I replaced my 21" wheels first with original 19" OEM Tesla wheels and then 19" TST's. On the 21's I was driving on OEM PS2s. On the 19's I'm using Bridgestone Potenza S04's. I drove ~5k miles with the S04's on the original Tesla wheels and did not discern a significant increase in energy usage. However, the majority of those miles were on the highway with the cruise control on. A few weeks ago I moved the S04's to the TST wheels. Since then I've noticed an increase in energy usage. I'm still collecting data, but driving around town without any aggressive moves I'm seeing around 350 wH/mile with peaks hitting 390 wH/mile. If you moved to TSTs I would love to hear from you and your experience. The TSTs are supposed to weigh the same or slightly less than the OEM wheels, so I'm confused by the increase energy usage. It may solely be from the tires and I didn't notice during the first 5K because it was all highway driving. A tirerack review stated the S04's are -1.12% less efficient than PS2. What I'm seeing seems to be more than that.