Did you ever meet the man?
Did you hear him in person?
Did you read any significant amount of his writings?
Did you listen to more than an hour of his debates or talks?
Or
did you only read disinformation about him?
I have read him. I have listened to his tapes.
What he says about Mormons is BS.
If what you think you know about Mormons depends significantly on Walter Martin, you are in a sad stae.