Spell check has its uses but it is not infallible. For example, such apps don’t know the difference between their and there, check and cheque, or bread and bred.
It’s disturbing to see the expression “As Much As We Are Lead To Believe” in the headline of an advertising post. Someone obviously thought it must be right, because the word processing program didn’t correct it.
Poor spelling affects your business. Take the time to get it right before you send it out.
And if you are less than confident about your spelling, call in a professional to make sure you get it right.