Great, I only needed one 2 gig for the entire US and 1 for EU, but the topos I used the 1 gig cards because Garmin limits your maps to somewhere around 2005 per card. The NT maps will do this but the topos for Canada took me 4 of them, 2 for US and 1 for EU. Alot of cards, that's why the pill box to put them in. But they come in handy when traveling. If you decide to get one PM me after you get one. Good luck.