I think the only thing Ive read about on this forum or maybe it was mazda3forums.com was a buddy club condenser, or a grounding kit, not too sure bout a voltage stabilizer. There is *supposed* to be some decent gains with the buddy club condenser.
May be a similar deal, the idea being to keep a stable voltage thruout system to
maintain all cpus, relays,etc at optimum operating spec, which supposed to help the car run better. Plus easy to remove for dealer visits
pivot raizin-good pricing and has a clear blue casing so you can see what you're using. Personally I didn't notice any difference with it on, but who knows.