You actually bought speakers @ XS cargo.
I am assuming then that any 4ohm speaker @6.5" Dia will work better then stock.
Bought mine @ Carelton Place in 07
Going in for my 25,000Kms service next week or so.
So far better then my 03 honda accord V6 as far as warranty issues. None on the GV lots on the Accord V6.

Gotta like the suzuki's
Cheers