Your bladder/hunger control must be way better than mine
30 minutes if you can drive right up to a charger. Do you think that will be the case once hundreds of thousands of EVs are on the road? Have you ever road-tripped in the summer and had to wait in line for gas, which takes minutes to fill? I have. Often.
Another problem is that, depending on where you are going, it looks like you might not be able to charge anywhere on the route. I found a map of locations here: http://www.teslarati.com/map/
Like the typical route between Denver, CO to Lake City, CO (255 miles one way) has no supercharger close. Would you modify your route to swing by the location? Or would you have a friend drive a gas car instead?
I have a 90D so I'd be able to make that drive in one go, although it would be close!
That being said, having done Seattle to San Diego recently (while passing thru Gilroy), I should have spent a day in Oregon or Norcal, 13hr days are just not my jam when it comes to driving.
For myself personally, I probably take 5 or 6 trips per year where I'm covering over 400 miles in a day. The time it takes to recharge the car would be a big negative to me. It's nice to be able to jump in the car in SF early morning and be in Seattle by evening. Not sure I'd even make it half way in an electric car.
I'm sure someone will comment "well this car isn't for you" and they are correct.