Below is the link for the company. Yes they are hub-centric... Yes they do use longer studs. IMHO by moving the wheel out the entire look is changed. You can see the wheel flush with the body panels and not just the tire. IMHO it looks like more expensive cars do. I am been told it slightly improves handling. I will have the 10mm in soon and will post better pics showing before and after shots.
WWW.ICHIBAUSA.COM - Hubcentric Wheel Spacers, OEM S13 5-Lug Conversion, Header, Turbo Manifold, Downpipe, Test-Pipe & More Performance Parts!