Ronnie for F.I exhaust if you keep it at stock height it will rarely scrape as the lowest point on exhaust is with tyres. The front lip would scrape way way more than the exhaust would ever touch ground.
With lowering on F.I you have to go through bumps and driveways slower than usual else you will bottom out whole car not only the exhaust
If given the choice to get exhaust again I would still go with F.I no matter how low it is just love the way it looks and sounds
Spacers are illegal so use of it depends upon you. 20mm and 25mm on 19's would stick out a lot and will get more attention but for looks they would be awesome
With lowering rear camber kit is worth it, I just lowered my car on coilovers, my rear tyres are like half inch in air from outside (will show in pics tomorrow after getting alignment done on stock setup)
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