San Mateo Supercharger wake-up call has shaken my confidence on Supercharger availability while traveling. San Mateo has 8 SC slots which were all, not only fully occupied, but had a lot of Teslas hoovering around, me included. Even if San Mateo had 20 SC slots, that wouldn't be enough. I had enough charge to get home, so after my second unsuccessful attempt to find an open SC slot gave up and drove home. But my take-away was SC availability should not be taken for granted. Now I'm questioning an upcoming trip to Roseville and SC availability. SC availability seems like a big deal now. Anone else concerned about the impact of the Model 3 release on future SC availability, even though M3 SC will be an option?