Ended up changing my vote from "Yes" to "No". Just paid almost $1600 to replace the O2 sensors in my E46 since it failed the smog check last week. Coupled with all of the other service trips made over the last 16 years or so, not to mention the gas I've used, I think I've easily paid the price of the car again. Of course it's unknown at this time how much the Tesla will end up costing me in the future, but with no gas, no smog check, no oil changes or leaks to pin down, no clutch replacements (okay, that one may not count as the BMW is still on the original), that's several sources of cost that will not translate to the Model 3. What will translate is the similar cost of factory labor charges as a BMW if/when service is needed, or so I gather from reading some of these threads.
Side note: Was given a brand new (41 miles on it!) X2 xDrive28i as a loaner while my car was in the shop for four days. If I didn't have a waiting order for the Model 3, I'd seriously consider getting the X2 despite the negative/differences. Handled real nice; a little bit more leaning in the corners than the Model 3, but it obviously doesn't have the acceleration as the Tesla (has a 2 liter turbo). Similar view out the back window (narrow), Ginormous amount of buttons, dials and knobs everywhere. Back seat was much more comfortable than the Tesla, especially in the area of thigh support. Front seats were 10-way adjustable and fit me like a glove. LED headlights were about the same as I remember with the Model 3 rental I drove a couple of months ago; which is to say, great. But with the upcoming news next week about AWD, I'm glad that I waited.