[SOLVED] Xubuntu 14.04 and Debian Testing. Which to own Grub2 Which will safely see the other?

Hi,

I had a situation in the past where one distro, that owned Grub2, stopped being able to see my other distro. Maybe the original kernel or userspace became too old to see the other OS's newer one. (Everything is on the same drive, different partitions).

I use xubuntu LTS's and want to install Xubuntu 14.04 with its kernel 13.3 or 13.14, for the 3 years *once it is released.* <- EDIT

Also, I want to have Debian Testing (xfce), installed which is kernel version 3.11.10-1 With Debian Testing being a semi-rolling release the kernel may change later when it is updated, I don't know ...

Question.

Which distro, Xubuntu 14.04 or Debian Testing should I attach Grub2 and which of the two is going to continue to see the other? (userspace may make issues, too.)

So, which distro will continue to see the other safely?

Thanks.