Your 205 will accept a MICRO SD card, do not confuse with a standard SD card.
I own Map Source U.S. TOPO 2008 and load a mapset from it, along with many waypoints I had created on my handheld Garmin gps. I did not include the waypoints I created out on the lake fishing. The waypoints become resident in the units memory. The topo maps did not, as soon as I removed the card the topo maps disappeared with it.
If I was going to fly to Italy, England or France rent a car and take my automotive gps with me, it would be worth the money to buy City Navigator® Europe NT – Italy on a Micro SD card and insert it in the card slot.