Garmin - Instinct 3 Tactical vs Polar - Grit X2 Pro

The Instinct 3 Tactical is the clear pick on raw spec strength, leading by 14.2 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 Instinct 3 Tactical if you care most about smartwatch mode and gps mode. The biggest gaps in its favor are smartwatch mode, gps mode, solar charging.

Pick the Grit X2 Pro if you care most about multi-band gps and ecg. Its strongest claims are multi-band gps, ecg.

There are no meaningful ties on the headline specs — every popular-comparison metric has a winner.

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