I have a Canyon BG #5 on my RPLXi and I'm a huge fan!!!
I did find that Ross is a bit on the optimistic side when it comes to backing capacity, though. Buy the #5 if you are looking for a large amount of backing.
By the way, not to plug anyone, but, L.L. Bean sells Ross reels now. If you go that route you not only have Ross's lifetime warranty, you have Bean's no questions asked guarantee as well. Redundancy is a good thing some times.