What's the micron rating on it? Filters with fiberglass filter media don't have symmetrical holes for when the fluid passes through. The asymmetry makes for a better filter. Also, you can't pleat the stainless steel in order to increase surface area like paper and fiberglass media.
Stainless steel filters are used for hydraulics as a tank filter BUT the inline filter with glass media somewhere along the way does most of the hardcore filtering.
2007 RX-8, Velocity Red, M6 Sport