Took a chance and used Direct Cycle Parts to order my exhaust, even though they had mixed reviews. Almost $200 cheaper than anywhere else, and free shipping. They shipped the day after I ordered and got it a few days later, couldn't be happier.

 

New Castle has failed to answer my emails, are slow and expensive shipping. I'm done with them.

 

http://cycleplicity.com/ also has mixed reviews.

I bought my Monotubes from them at a superb price - order processed promptly and reasonably quick free shipping.