Dual boot is not impossible on Samsung Galaxy devices. You can do so on Galaxy S3 and S4. Why not Samsung Galaxy Note 2, right? Yes, you can do so on Galaxy Note 2 on both N7100 and N7105 models with Devil Kernel. Enjoy both TouchWiz firmware and AOSP ROM like CyanogenMod at the same time.
Wow… The installation guide looks long and details. Be sure to take your time to go through all of them and read the FAQ too. Ready? Head to XDA Forum to know more – link.