Replaced my Montana 680t with a new 700 today. The initial excitement is wearing off pretty quickly. Did the software update, then started on the map updates. It asked me to insert a new microSD card to hold TopoActive 2020.20 and warned me that if I remove the chip, the update would be unavailable. My question is . . . how can one use a 24k topo microSD and an updated version of TopoActive at the same time? Doesn't seem possible.