I'm not sure what DSLR to get?

I have a budget of £6000 to get a good camera and lens(es). I have been trying to choose between the canon 5d mkiii, nikon d4, nikon d3s. The lenses i was looking at are the sigma 150-500, sigma 300-800, sigma 500mm, canon 100-400 and i'm open to suggestions on other dslr's and lenses but i really want to keep it to these 4 cameras

What kind of experience do you have shooting with a fully adjustable camera?

If this is your first one, maybe spending £6000 on your first camera and lenses, may not be a good stratagy.

If you do have a lot of experience, you may NOT want do depend upon opinion, but on your own research.

I use a D3 and D300 (my D800 is used mostly for shooting in the studio) and the following lenses.

* 14-24 mm wide angle
* 24-70 mm f/2.8
* 70-200 mm f/2.8
* 300 mm f/2.8
* 200-400 mm f/4

Those lenses allow me to shoot just about every type assignment most photographers get during a year.

I also have a macro lens I use when I need to shoot medical or scientific assignments.