Sorry a bit late with the info on this, just saw the topic!
Fujitsubo is made by the same company as Nismo & shares some of the manufacturing bits & bobs. It is very similar to Nismo but a lot more expensive depending on which one it is. There are about 3 or 4 different types availiable for the z, the seller doesnt tell you which one it is. The cheapest is an all stainless steel one which is about £600, the most expensive is the Super Ti which is all titanium & about £1500 approx, & a Super Ti Hybrid (which I have) which has a stainless steel back box & tips, the rest is all titanium & is approx £1000. They also do a couple of Race exhausts, non road legal (I think legalize r ones). The one on ebay looks like the all stainless steel one.
A couple of related links:
http://www.hyeline.com/fujitsubo_super_ti.htm
http://www.hyeline.com/fujitsubo.htm