There shouldn't be any other differences, but being a bit paranoid I don't like to trust images from just anyone. I did however just discover a post from someone called zitstif that includes a good guide on how to resize it yourself here - http://zitstif.no-ip.org/?p=484

Keep in mind that if you're going to stick with shrinking the image and using vfat, you will reach a cap at 4gb for how much data you can keep in the image. You won't have a lot of room to add things.