If everything else remained the same, but you were able to bump up your monthly extra payments to $60, then you would save $2,638 in interest and finish paying off your mortgage 19 months early. That is the awesome power of reverse compounding. Here is a terrific calculator for anybody who wants to investigate how much time and money prepaying would save them.
The third reason I am against the credit life idea is that the premiums for credit life insurance are usually much higher in relation to what these policies pay out than regular life insurance policies. Some consumer advocates have even labeled credit life a "scam." I won't go so far, because I define scams as fake offers meant only to steal your money. Credit life is more of a rip-off. It's a real product, but usually terribly overpriced and misunderstood. You would be better off shopping around for a new standard life insurance policy, to see what you can get for $40 a month. I hope this answer gives you –and everybody reading—more clarity. Good luck!