Since my ride is lowered, the oem front and side underspoilers seem to scrape on driveways and high speed bumps so I want to remove them. Is there any noticable difference in aerodynamics or other factors for anyone who has removed these 3 pieces?

 

You have the SE?

Aerodynamically, no I don't think you're going to notice any difference. Perhaps a tiny bit of weight savings, but it won't be noticeable unless you follow up with more weight reduction.

Some thing to note: The instructions for installing the SE side skirts I believe requires drilling into the rocker panel. So, unless you installed it yourself and went a different route (not drill into the side of the car and used 3M tape instead for example), there may actually be holes there which will suck.

How low are you? You must be really low if you're scraping the side skirts. If you're just scraping at dips/speed bumps/driveway entrances, try to adjust your entering/exiting technique and see if that helps.