Another thing to look out for if you feel you are low on power is the secondary intake flap. Make sure that the flap is init's closed position when installing the cone filter otherwise it will not close and will hit the cone filter at low RPM.
My favorite tire brand is Hankook. I have them on all my cars.
I gave up on Michelins, Pirellies and even Contis! I would consider them for track use if I ever tracked my car.
My Hankooks lasted 18 months, and the rears are almost due for a change.
I've installed RSR springs on my GSF and love the stance.
I have installed springs on many of my sedans in the past, never did I ever have problems with shocks. I trust these products.