Holy cow. That's really disappointing. I mean, I know that copper transfers heat better than stainless, but I didn't know that it was THAT big of a difference.
Maybe your faucet's aerator is severely restricting flow?
I know stainless is awesome and everything, but if I were you I'd send that sucker back and get one made out of copper. Or save yourself a ton of dough and make one out of copper, and make it longer than 12 feet. Copper has three things going for it in this particular application that stainless steel lacks:
1) Heat transfer. Apparently copper is way better than stainless in transferring heat.
2) Yeast nutrient. Copper is a very beneficial mineral for yeast. If you don't have any copper in your boil or post-boil setup, then I'd recommend cutting a 2-inch piece of copper pipe and just keeping that in your boil kettle.
3) Anti-bacterial. Copper is naturally anti-bacterial, so you would THINK that stainless CFC's would be more sanitary, but I don't think that this is the case.