It is a sucky deal, send me the sellers info and I will give him hell for trying to take advantage of you
OK, the 478 is the superman of the 276/376/478 series, it has ONBOARD the detailed street maps of all of N America. 276 owners pay $90 for, then have to spend another $120 for a data card that will only hold about 1/5 of the N America maps. Plus the screen is MUCH brighter at full illumination.
For the same $90 you can get lifetime updates and do NOT need a data card. But the new maps are too large for the entire NA set, but will hold lower 48. So unless you need the latest gas station, hotel or restaurant locations, just keep the maps on it. Lets face it aside from a few round-abouts most streets are in the same place they were 10 or 20 years ago.
Now, if loading anything but the NA detailed maps (city Navigator), you will need a data card, Topo, Europe, or other regions of the world.
If in the market, jump on it!