What issues do you have with spam? Personally, I get maybe 1 false-positive spam email per year with Gmail, and maybe a few false-negatives (which are less of an issue anyway), for an accuracy rate in the 3-4 9s range. So I'm intrigued as to what you're doing or where you encounter the inability for gmail to distinguish between real communication and spam.
What issues do you have with spam? Personally, I get maybe 1 false-positive spam email per year with Gmail, and maybe a few false-negatives (which are less of an issue anyway), for an accuracy rate in the 3-4 9s range. So I'm intrigued as to what you're doing or where you encounter the inability for gmail to distinguish between real communication and spam.