Hey, if anyone is interested in the race seats and harnesses out of the RSX, let me know. Both seats are in great condition and can come with or without the Corbeau RSX seat brackets and double locking sliders. The FX1 Pro is a narrower seat. It fits me very well (32" waist), but I also liked a very supportive seat without much extra room. YMMV. I think they're reasonably comfortable and have made 8+ hour road trips in them.
With the brackets and sliders, they come out to about 30 lbs. per side. Together, they shave about 40 lbs. from the RSX. With some lighter aluminum side mouts (which the seats will work with) you could get down to 25 lbs. a side for a dedicated track/autocross car. The seats are not FIA certified if that is a concern for you and any track days.
The harnesses are in good shape and were used for autocross and daily driving for about two years. There is some fraying on the lower section of the drivers side harness, but it does not look significant enough to compromise the safety of the harness yet. Still, if you want to be safe, you can always wear the stock belt on the street and just clip in the harness for autocross events. The harnesses do hide easily behind the seats when not in use if you so desire.
New, this whole setup would run about $1200 + shipping from a site like soloracer.com. Given that they are used, I would ask $500 + shipping for the seats (maybe less without the seat brackets) and $100 shipped for the harnesses. Also, I would very very very much like to not ship these as the seats are just too large to do so easily. If you know anyone else local who might be interested, that'd be great.