My Mugen Seat rail came in recently.  The Mugen seat rail are a thing of beauty, it’s very light, and the mechanism to move the seat back and forth feel exactly like OEM.  The downfall unfortunately is that it only fits perfect with Mugen seats.  With the Recaro SPG seat, it is a too narrow, I had to use washers to make my seat fit, I’m currently researching other spacers to make the seat fit correctly and look decent.

The OEM seat bracket fits perfectly!