You may get tired of a machine that only does 4" designs and will probably outgrow it soon. You may want to look into one that has a USB port to hook up to your computer. A reputable sewing machine dealer might have a good used one at a reasonable price and it is certainly worth looking into further. IMHO. As far as Brother machines go, I have the 8500D and it is very easy to use. I have never had a problem with it and wouldn't trade it for anything.
Leatheflea is right about the cards being expensive. Prices are brutal. After you decide which machine to get, you may want to look into Embird, a digitizing program that converts embroidery designs.