if you live on the north side (like near the 1960 area) you might get caught as there a few troopers that mess with people for that type of thing. it is only a fix-it ticket. I am down south and never had any trouble. when I got inspected they didn't even look under the car.
oil companies and places like jiffy lube want people to believe you need to change every 3000 miles. It is just not necessary these days for "normally" driven vehicles.
I don't have any clearance issues with mine.
The only problem I have is the long rod that attaches to the tip (and goes into the rubber hanger) does not stay tight and it rattles against the tip sometimes.
Started out in engineering but after a couple years I decided to switch. Got my B.A. in Economics from the University of Texas back in '03. Minor was Business Foundations(accting, mkting, business law, and mgmt).