Just tether to your phone and get faster speed. $130 extra for 3G function and it's medeocer speed is not worth it. Beside, hot spots are everywhere and expanding.
I use an xperia x10i that uses tmobile's hsdpa network bandwidth and I can download very fast when I tether my iPad. In the speed of 500kbps to 1.5Mbps. Very convenient and reliable connection when you need it. But not all the time, wifi tether kill battery fast!