Timing the right time to pull the trigger with Tesla, is the sooner the better, with the understanding, the model S, is always getting better, if you search the numerous threads on this site, Tesla will change something they do on the production line when ever they find a better part, I don't know how to insert a link, but google tmc model s changes by year, and you will see the constant updates thru the year, I think what we are afraid of is a big refresh, like the front nose, AP1, AP2, while the interior has constantly been changing too.... like the seats...
So, just jump in and get one, and enjoy it.... thats why I said the sooner you do it ... if you can, lease it and then get a new one in 3 years
there will be a lot of changes in 3 years thats for sure... look at the growth of Model S
remember it went from 40, 60 and 85, then 70-75, 85-90-100....