Amazfit - T-Rex 3 vs Samsung - Galaxy Watch 7 (40mm)

The T-Rex 3 is the clear pick on raw spec strength, leading by 35.9 points on the Mars Score. The margin is wide enough that the underdog only makes sense if its individual strengths line up with what you specifically need.

Pick the T-Rex 3 if your top frustration with your current device is running out of charge before the day ends — endurance is the lead spec here. The biggest gaps in its favor are battery life, display size, water resistance.

Pick the Galaxy Watch 7 (40mm) if the display is what you stare at all day — refresh rate, brightness, or sharpness is where the difference will be most visible. Its strongest claims are peak brightness, weight, ecg, among others.

Both ship with comparable spo2, so those specs don't separate the two — focus on the differences below.

Bottom line: the T-Rex 3 is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.