Reduced the rough idle I was experiencing. At stoplights, my engine used to vibrate. The RPM would hunt up and down. After installing this, the idle is smoother. Less vibration in the steering wheel. More comfortable at red lights.

No effect on my car's computer or error codes. I was worried it might confuse the ECU. Scanned for codes after a week. Nothing. No check engine light. No warning messages. Works transparently.

Noticeable improvement in brake sensitivity. I didn't expect this benefit. The description mentioned it, but I was skeptical. My brakes feel more responsive. Less pedal travel. Not a replacement for new brakes, but a nice bonus.