It will depend on your car. With the 30 mm spacers you'll be at a 5.1" backspace, which should be about perfect for a stock rear set up and a 9 inch rim. But it will come down to assembly line tolerances. I've seen people run a 5.5" backspace and be just fine in the back with stock suspension, but I've also seen cars that couldn't clear a 5" backspace. It will be pretty close, so you may even clear one side and not the other...
The front looks good huh? How does the tie rod clearance look? I want to run 17x9's in the front too, I think mine will be a 5" BS. The only issue is I have dropped spindles, so the tie rod may be close to the lip of the rim again...