I can speak personally for pocomoke city, as I am a Pocomoke City Police Officer, Volunteer FF in the Fire Company, and the President of the Volunteer Ambulance Co. Our police dept would definetly enforce lights on personal vehicle, as well as the fire company SOG's and the Ambulance Co SOG's strictly outline who may and may not run lights. There are actually several laws in the MD Transportation Article that cover red, white and blue flashing lights, so the fines could actually be numerous.
As for using your Emergecy Flashers, aka 4-ways, we do allow that, as long as the people using them operate their vehicles with alot of due care. All of our police officers can overlook a little speeding etc to get to the firehouse, but if it's excentric, people will get fines.
I do know that Ocean City Fire Company will not tolerate flashing red lights on a vehicle, as well as the OCPD won't tolerate it... so the answer is gonna be no. I do not know if OCFD allows the chiefs to operate lights in their personal vehicles as all of them have Fire Co issued vehicles to respond to calls in.
Chris