MTC cans are the supported manufacturer on the forum, its use to be Carbon Can Company (CCC) but that fell through with the changing ownership.
Anyway have a look at the MTC website and get in contact with captomoto for a discount code. I they should be cheapest with the discount but that doesnt mean a lower quality can. They do a fair amount of shapes and lengths so take a gander at there website.
Hopefully someone will be along who owns a pair and can tell you what they are like.
http://www.youtube.com/watch?v=zE8VboqEjsY