For those of you unfamiliar with the "Principle of Polarity," it states that what was once resistance becomes support and vice versa. Looking at a logarithmic monthly chart of TSLA, there are unquestionable and very significant levels of resistance that have finally been broken. Generally, when iconoclast stocks hit all-time highs, they don't stop. If you're waiting for a significant pullback, I don't believe the odds are in your favor.
If these levels were established on a shorter time frame, I might be less enthused. If everyone was already driving a Tesla and the name had become ubiquitous around the world, I might be less enthused... neither are the case.
The rate at which Tesla is expanding production GLOBALLY... the rate at which they're acquiring companies to further solidify their position and corollary LEAD in this industry... these are the hallmarks of decade-long bull runs. I've never been this excited about owning stock in a company.
However, I would always advise an exit strategy. I'm watching $390. I expect it to drop back to that level. If it does, I'm buying as much as I can. If it drops below it, I would get out and reassess as the chart evolves.