Yeah man..do whatever you feel comfortable doing.
The bulk of people pay in cash and I think the rule of thumb is to own what you can afford. I may WANT the newest Stern LE or something. But I can't afford that much in cash. And, like anything else, new pins will likely depreciate.

So what happens if you find a dealer who will finance a pin for you through some plan...and you finance, say, an $8k pin. And in 3 months you want to sell it, but you still owe money and it's only worth half of what you paid for it...
But to each his own.

The challenge is not having the funds for it and not having credit for it.