I learned the benefit of wrap on the rear bumper of Model S when accidentally backing into a cement planter. The wrap was torn, but the paint untouched. The lower charcoal plastic and chrome metal were replaced along with the wrap for under $1000. No repaint needed.
How different when a slight 1 mph touch of the side rear bumper that was unwrapped occurred. It still has the scrape and the missing paint. Would have been avoided with the wrap.
I look forward to the sensors on Model X that will help avoid such incidents. But, the savings with wrap can still occur when other vehicles or objects collide with the surface. It is money well spent for my enjoyment of the vehicle. Easier to clean and less worry about scratches.
The cost to benefit ratio will vary depending on the situation. Consider a partial wrap, especially for front, hood and rear bumper areas. Side mirrors and fender wheel well zones were also protected on the Model S Signature when Tesla Motors offered the wrap.