Now that I'm actually going to start riding my bike (well mountain bike) off the pavement I figured itd be nice to have the Topo map. I currently use the 2010.2 CN on a 2gb microsd and it takes up almost the whole thing. I was thinkin of a 4gb high cap but Im worried it wont recognize it. Does anyone use one? Will there be any funky display issues with having the 24k topo and CN both on one sd?