Cosmetics... People are paying out the ass on eBay for the older ones with a gold box and centaur graphic. The new ones are a silver box with no graphics. The new ones still look pretty cool, considering how simple they are. But for $400 - $500 cheaper, I'd rather have the new ones.
Somebody might claim the circuits are different, but I don't know for sure. I know that I've read Finnagan's own words and he seemed to have put years into the circuit and lots of money. I can't see him making drastic changes to the circuit. It'll probably turn into a Big Muff debate... which is ridiculous.
$350 for an OD/Booster is expensive, but considering how much other pedals cost, especially boutique pedals, I don't think it's that bad. I think a lot of people expect an expensive pedal to have a bunch a switches and knobs, lots of blinking lights and crazy ass sounds. Fuck that. If it's a good pedal and does it's job well, and you like it, it's worth it. And if you can find something for a lot cheaper that you like better, good for you.
I'm still shooting for one of the new ones. I like the way they look and I feel certain I'll love the sounds. If not, like Big John said, there's always eBay.
Where do you get those parts?
I'll pay ya $60!!!