I used to run 16x9 et30 all the way around. I needed extended lugs and spacers in the rear to clear, but overall I was happy with it.
My current set up 16x9 et15 (front) 16x9 et25 (rear). Its perfect for me, but for the "purists" a little tire stretch is no good lol. I have minimal stretch on my setup. Today's hella flush craze kills it for those of us who really dig the low offset wheels. I've had low off set wheels before the hella craze, and will continue to have them in the future. Just not that super extreme, tire stretch, skate board look.