Garmin Pas Cher vs Cher : Test de Précision GPS

Day 21: GPS Accuracy Showdown

I ran the same route wearing both a Vivoactive (single-band GPS) and a Fenix (multi-band GPS) simultaneously. Here's what I found.

The technology difference

Single-band GPS (Vivoactive, Forerunner 55): Uses one frequency from multiple satellite systems (GPS, GLONASS, Galileo). Works well in open areas.

Multi-band GPS (Fenix, Epix): Uses multiple frequencies simultaneously. Much better accuracy under tree canopy, near buildings, in urban canyons.

Test results

• Open road: Both tracks almost identical. Difference <0.5%
• Under trees: Fenix noticeably cleaner track. Vivoactive had some drift
• Total distance recorded: Identical on both watches
• Battery used: Vivoactive 3%, Fenix 4% — multi-band costs more power

Verdict

For road running and flat terrain: single-band is fine and you'll get more battery. For trail running, forests, or dense urban areas: multi-band is meaningfully better. The Fenix costs significantly more — but the GPS difference is real.