Need equipment help from you

Hello everybody,
since I did a lot of comparison and test, I want to ask you for an advice.
The 3 following systems are on the list:

4 shots leveld for a full sphere , NPP-adaptor: Nodal Ninja 3

1. Canon 40D with Sigma 8mm
2. Canon 5D with Tokina 10-17 (or Nikon 10 -> both have to be shaved)
3. Ninon D300 with Sigma 8

I am using a D80 with Sigma 8 now and I am not stisfied with the noise
of the camera. ISO 200 goes well but 400  is already unaccaptable.
All images I saw where camera-jpgs - so not really  a true
competition, and the RAW I got where not so much better than mine (40D
RAWs).

Like Hans and Michel stated: the Tokina is remakable sharp - i would
prefer this lens instead of the Nikon 10.

So I am standing here a little confused and don´t know where to go.
The 5D is a little heavy for the NN3 - but will work I guess.

Can someone help me ??

Thank you
Ciao
Mike