(G) Plastic lip under front bumper?

I was just wondering if the plastic lip that's under the front bumper is good for anything.
Mine seems too touch on alot of speed bumps and most curbs and it's starting too look a bit loose.
If it falls off should i have it replaced or is it not necessary???
All of you who have lowered the Stilo, havn't you had any problems??
Thanks

Mine is currently missing and you can see the ugly edge of the sump guard and also the start of two metal strut things.

Keep it on, it looks **** without it

I think it's there to help the airflow under the car.

Mine keeps scuffing off things too and I noticed there are a couple of cracks where it's mounted.