Another

for the Canon 5D mk2.
I have the older canon 15mm fisheye attached and can't fault either for image quality. I also use the same combo inside a Ikelite underwater housing with 8inch dome although not for 360's.
The menu is pretty crap on the camera so just install the Magic lantern software. The software gives you more options plus adds more than the dreaded default 3 bracketed shots.
Depends on your budget I guess. If you want to save cash I see the camera is now at MK 4 so people will upgrade and sell their old one.
I also have the Ricoh V which is fantastic for those hard to reach places and better than not having the shot at all.
Andrew