Wife's car no need to mess around much la. FC good but install SC then surely go south already. She will probably also complain why engine becomes noisy. Like one of our Mark X Club guys also, he installed SC kit but only used very shortly as the wife keeps complaining that suddenly the car sounds so noisy with all the whining and swooshing. Now that my Mark X I give to my wife to drive, I also stop thinking to mod it already coz she won't appreciate it!
Btw weird choices of cars you have there.
My wife used to drive perdana rvr turbo, and estima supercharge. She love the spectra 5, but she also complaint of pick up too slow.
And for noises, i think she's used to it.

As for the car choices... Well... It's just hard to explain.