No, the HighPro Polariser features an ultra-slim 3.5mm frame specifically designed to prevent vignetting on wide-angle lenses as wide as 16mm on full-frame sensors.
Yes, it features a dual-sided nano-coating that is water-repellent and oil-resistant, making it easy to wipe away sea spray or fingerprints during outdoor shoots.
You will typically lose between 1.2 and 1.5 stops of light. Most modern cameras will automatically compensate for this via TTL metering.