How long do your vehicles last?

[Vimp]

If you go get a Basilisk for example and you take it out to some trees and get off to snipe for a while is it a real liklyhood that your vehicle will just fade away on you. Then when some one gets annoyed with you and comes at you in a vehicle and you turn to your ride to get away, you'll just turn around to find out your ride has dissapeared on you and your then a sitting duck to be plucked by any enemy vehicle in the area.