Base On my experience, MSE is not basic already build up protection in Windows, it it self is a AV produced by microsoft. anyway, i never recomended to have two AVS with Both Real Protection are active. It might causing a conflict. And based on my experience, fro the time being, with PC of my csutomer which have both av active on its Real time Protection. They indeed conflict each other. And causes the computer to freeze.
Most antivirus products will do a better job protecting your system. Having MSE enabled will cause slowdown and possible conflict.
You can use malwarebytes if you like to have better detection with MSE enabled, otherwise better disable it.