I took mine out long ago, I do not recall the weight saved but much less than expected but I am a weight reduction junkie so might take it back out. I put it back in at the time because there was no simple solution to make it look right at the time.
My car has the rear seat delete and many other weight reduction mods, 175lbs or so removed, and the front to rear weight bias was to high so I left it in but since then and most recently the biggest share of the effort I have moved 50lbs from the front to the rear at great time and cost so a wiper delete would not gain as much as before.
I might be selling the car soon so going to leave it as is, if I keep the car I will delete it when I design the hatch mounts for the rear race wing I will install, APR GT200 Spec 48" wide mounted high and far enough back to be very effective.