Hello All, So I have picked up a set of 19" slipstreams from an owner here on TMC to augment (and potentially replace depending on how I like them) the 21" staggered turbines I have on the car now (a 2013 P85+ - I should have the older TPMS units). The slipstreams do not have the TMPS units. I think my options are: Options for The Parts Themselves Swap in the TMPS units from my existing 21s Buy new TPMS units from Tire Rack (note: they have them on sale for $50 each vs. their normal $75) Buy new TPMS units from Tesla. I "hear" they have been $50 in the past, but not sure what current price might be. Buy a set of what appear to be "programmed" ITM units off E-bay for $171 (see example here: Set of 4 TPMS Tire Pressure Sensors 2013-2016 Tesla Model S 60 75 90D P90D Change to NEW style TPMS units to get the actual tire pressure readings to display on the instruemnt cluster Options for Labor and Configuration Options Get local tire store (Discount Tire - who generally does a good job for me at the store I frequent) to install and "configure" them to the car Get Tesla service center to install and "configure" My Questions Option 5 - Is option 5 (for the parts) really a valid option ( I see where some people have had it done, while others say they Tesla no longer does this)? If so, does anyone have an idea on cost? If insanely expensive, I'll likely just pass. Tire Rack vs. Tesla - Has anyone used the sensors from Tire rack? Honestly, I am sure they are the exact same part Tesla is selling? Configuration/programming - What does the "configuration" entail and can a local tire chain (discount tire) do it or does it have to be done by Tesla? I know there is the little handheld tool Tesla used to sell to "program" them, but I've also seen folks claim they were able to just use the on-screen reset process and start driving (and they code themselves). The main attraction with the Ebay units might be the fact they are pre-programmed. Not sure if the fact that I am going from 21 to 19 means something else is needed in the car itself. Originally, I just assumed I would use my existing TPMS units, but now I'm considering just getting new ones so I can have two functional sets with no hassle if I decide to swap back and forth between them. Happy to hear any other comments as well. Thanks!