I own the 5d MK2 and I can shoot large JPGs at 3fps for 5 minutes without stopping
and now I'm looking to rent or buy a DSLR that can shoot at the highest frame rate at the best quality ( JPG or RAW ) for at list 3 minutes without stopping. I think I would be happy with a DSLR that can shoot 5 to 7 fps continuous.
Hmm... I'm thinking a Nikon D3s with its small 12mp and pro-FPS might be able to do the trick. Hopefully it has a larger buffer depth. You have to remember that the larger the MP file is the more data it has move across the pipe and into the CF card.
Therefore a 1d4 with 10fps might fill the buffer faster since it has 16mp. I don't know. Hence my suggestion for a 12mp d3s. Actually perhaps a 1d3 might be worth looking into.