Is this speaker set up ok?

TRINADS

I have the Polk Lsi15's for fronts, LSiC for center, but 2 pairs of FXi3's for my surrounds. I know the surrounds are not the LSi Line, but will it make much of a difference? I absolutely love how they sound, but how much of an improvement would I get getting the LSiFX surrounds? I am currently pushing all of the speakers with my Pio Elite 82TXS, I know that I need an amp to power the fronts and center, as they are rated at 4ohms, the pio Elite does a decent job, but I know that they could sound much better with a proper amp, but regardless, I was just wondering on the surrounds, as would it be worth the money to upgrade to the LSiFX's, or just stick with the FXi3's? Would I even notice the difference with the 'voice timbering', or does it not matter since they are all Polk's?

Ricardo

Spend your money in a separate amp for the front stage. That will make a difference you'll be able to notice.