I have both, and they are very different pieces IMO.
The 5070 more classic in design and execution, while the 5960 is a very modern Patek from an aesthetic and technical side. Though I really like both, I find that I wear the 5960 more, and if I had to choose just one, it would be the 5960.
I doubt the 5960 will ever be considered as special as the 5070. It simply departs too much from Patek's history, and will be made higher numbers than the 5070 was. Patek themselves set easier manufacture a goal for the 5960s calibre.
Id say go for the one you think youll wear the most.