I'm in a similar boat as a growing number of others in these forums. My '16 340i M-sport lease is up in October and I'm wavering on taking delivery at the beginning of the cold weather season (snow comes in Nov and lasts through Mar); I'd need to immediately buy snow tires, and maybe wheels to avoid winter damage to the 20" P3 wheels. I can extend my lease for 6 months or buy something temporary to flip in March or April next year and get a MY2020 P3 then. I can't seem to make a decision one way or the other.
Maybe some news will come out in the next couple months that will make the decision easier.
Sounds like you need to move to St. George. Nice thing about living in the desert... we don't have to shovel sunshine off our driveways.
You might also want to consider the P3D- (aka, the "Stealth" Performance Model 3), as it doesn't come with the big Brembo brakes that the standard Performance Model 3 comes with. You're going to have to find snow tires for your 20" wheels, as the big Brembo brakes makes it impossible to put smaller wheels on the standard Model 3 Performance.
There is a small possibility of us moving from St. George to Salt Lake in the next few years, and that was one of the factors that made me want to go with the P3D-... the car doesn't have the big Brembo brakes, and I can't put 18" wheels (mine came with 19") with snow tires on it easily if needed.
You might want to take a serious look at the P3D-. It's a Performance without the Performance suspension, 20" wheels, Brembo brakes, performance pedals, or spoiler.
I was actually shopping for the standard Performance Model 3 when my Sales Advisor told me about the "stealth" Performance. I was immediately sold when I heard that it did *not* have the performance suspension. The fact that I could put smaller wheels on it was just the proverbial icing. Oh, and the lower price didn't hurt, either. ; )
If you ever find yourself in St. George, send me a PM... I'll take you for a test drive of the P3D- "Stealth".