exhaust header for spitfire

[Jeff Gruber <jgruber@demainsoft.com>]

I'm thinking of buying Trevor's exhaust manifold to replace the one I broke 
on a bump.

His manifold is intended to boost performance, but I'm thinking of durability.

The original manifold is cast iron and by nature brittle.  Trevor's is 
steel, from what I can tell and less like to crack the next time I hit a 
bump too hard.

Any opinions on this idea?  Any pitfalls and precautions?

Thanks.

Jeff Gruber