I would say the best way to make this decision is to create some scenarios (lease vs purchase) and make your decision based on the facts that presents.

If its personal use then obviously you want to take the option that will take the least off your bottom line.. if its for business then that can be a different story (well it is here)

__________________
2006 E53 Kalahari Beige, X5 3.0d Sport [sold] | MY13 Audi A1 Ambition | 2004 911 GT3| W124 Estate