Having three of the original RPLX's, I never got used to the i's. Seemed like the tips were too soft to suit me. And I didn't want to have to re-learn to cast the RPLXi. I have heard some say that the tip on the i just gets out of the way when fighting fish so that in essence, you are fighting with a shorter, beefier stick. Three piece vs. four is just something you learn to deal with.
The Xi2 sounds like the better of the two.
I fish because the voices in my head tell me to