Wheel Fitment Query

[nooge]

Hi all, just curious to know if 17" 8J ET30 wheels fit fine on my 9N3 sport? I currently have 17" 7J ET38 but I'm new to the whole fitment thing as the 17's came with my car. It is lowered 15mm (on factory sport springs) if this makes a difference. I have done some research on the internet and have a basic understanding of it all, but some guidance would be nice. Cheers in advance guys!