definately challenge that, i lived in maryland since i was born til i turned 18.. and have heard many many many exhausts louder than a PV.. there were a couple guys in my neighborhood who would drive down the street a gear too low to see how many car alarms they could set off around 11-12 at night...

yeah, ive been pulled over for windows being tinted too dark... lucky for me, there happened to be a friend of mine in the squad car.. cop still said that if they couldnt recognize my face the windows were too dark, so i had to take it off and tint it again a little lighter (35% is legal i think)