Not sure a supplement saves that much. $3000 is the max annual out of pocket for tricare. As far as I can tell, supplements cover the out of pocket. If the supplemental premium is $140 per month with a 300/600 deductible, that would yield a family annual cost of $2280 (140x12 + 600). By my math you only come out ahead if your medical costs uncovered by Tricare exceed $2280, and the insurance only protects you for the last $720 until you hit the Tricare max out of pocket of $3000.
Anyone see it differently?