As with any new device you wonder if you got the right version The iPad has 3G version is on it’s way. I opted not to get 3G. So far it has been great. I have used my iPhone as a tether, to have wifi at all times. The MyWi application is great. You just setup your own hotspot.
http://www.rockyourphone.com/index.php/mywi.html?feat=y
This is a good option if you are unsure of which option to get