I've got a sway bar from a Monte SS, no clue if it's an F41 or not. It is a heck of a lot bigger than the stock one though 8) Havn't installed it yet though, one of those "winter projects" that'll be getting done in a rush at the last minute
I felt a difference when I put on the rear sway bar. I also added the jounce bars and I recently purchased the stabilizer bar that goes side to side in front of the jounce bars and the engine bay bars.
I like bars.
I have a complete sway bar setup on a junk 79 Monte Carlo but they are the smaller bars. But if you don't have any at all then this would be an upgrade.