If you are serious about spending the money, you need to drive both. Fly to someone who has each and is willing to let you take a ride. Next, see how long it takes you to get a few random parts for each by calling around locally and asking availability. I dunno, water pump, an injector, ecu, AC compressor, power steering pump? If you wouldn't plan to do the work yourself you might also ask the same of a repair shop in a random place you may someday travel to... you will then have some input based on your own driving assessment and real world serviceability, not conjecture from the internet.... and you will go with the V-8