Rates are different probably due to placement, front vs rear. As for being liveable, that's up to you. Guys drive in slammed on coil cars all day. Being that you say its mostly highway I would say go for it. You shouldn't be hitting messes up roads at any high speeds in any car, unless you got lots of money.
Two Three Zero
FRPP, "Stealth" CAI, Debadged, wider tires, louder stereo, turbo mainfold in the wrong place...