Apple - Watch Ultra 3 vs Garmin - Fenix 8 (47mm)

These two are nearly even on the Mars Score (65.3 vs 64.3). The decision is not about overall quality — both clear the bar — it is about which specific trade-offs fit your use.

Pick the Watch Ultra 3 if the display is what you stare at all day — refresh rate, brightness, or sharpness is where the difference will be most visible. The biggest gaps in its favor are peak brightness, display size, weight, among others.

Pick the Fenix 8 (47mm) if your top frustration with your current device is running out of charge before the day ends — endurance is the lead spec here. Its strongest claims are battery life.

Both ship with comparable ecg, spo2, water resistance, so those specs do not separate the two — focus on the differences below.

Bottom line: there is no wrong answer here — match the spec advantages to how you actually use the product. The Mars Score parity says both are well-rounded; the differences are about trade-offs, not quality.