Amazfit Cheetah 2 Ultra vs Garmin Fenix 8 Pro: Which GPS Watch Wins?

Overview

The Amazfit Cheetah 2 Ultra targets serious runners who want advanced biometric tracking, including muscle oxygen saturation, at a mid-to-upper price point around £400. The Garmin Fenix 8 Pro is a flagship multisport and adventure watch at roughly $1,000, built for athletes who need the broadest possible feature set across running, trail, triathlon, and expedition use. The core tension here is value versus ecosystem depth.

Specs at a glance

Price tier: Amazfit Cheetah 2 Ultra approx. £400 vs Garmin Fenix 8 Pro approx. $1,000
GPS: Both use multi-band GNSS; specific chipsets undisclosed by either brand
Battery life: Neither review confirms exact GPS hours; check manufacturer pages before purchasing
Heart rate sensor: Both use wrist optical PPG (measures blood volume changes via LED light), not electrical signals
Unique sensors: Cheetah 2 Ultra adds SmO2 (muscle oxygen saturation); Fenix 8 Pro adds skin temperature and LTE connectivity
Display: Fenix 8 Pro uses AMOLED touchscreen; Cheetah 2 Ultra display type unconfirmed
Water resistance: Fenix 8 Pro rated to 100m; Cheetah 2 Ultra rating unconfirmed
LTE: Available on Fenix 8 Pro with a separate monthly subscription; not present on Cheetah 2 Ultra

GPS and tracking accuracy

The Garmin Fenix 8 Pro has a well-established reputation for reliable multi-band GPS lock in difficult environments, including dense forest and deep valleys. At $1,000, that is expected, and the watch delivers consistently.

The Amazfit Cheetah 2 Ultra's GPS performance data is limited in available reviews, so a direct head-to-head comparison on satellite accuracy is not possible here. Buyers should seek independent field tests before committing.

On heart rate accuracy, the Cheetah 2 Ultra has a concrete edge in the available evidence. In a HYROX simulation at 33 degrees Celsius, a genuinely harsh environment for wrist optical PPG sensors, it produced near-zero bias against three reference devices: the Whoop MG, the Garmin HRM-600 chest strap (an electrical ECG-based reference), and the Polar Verity Sense optical arm band. That result in high heat and high intensity is meaningful. The Fenix 8 Pro's Elevate sensor performs well at steady-state efforts, but no equivalent stress-test data appears in the available review material for comparison.

Battery life

Neither review confirms specific GPS recording hours for either device. The Fenix 8 Pro review explicitly flags that its AMOLED display costs battery life compared to MIP-screen rivals, and that competitors at lower price points post significantly longer GPS times as a result. If battery endurance is a priority, verify current figures directly with Garmin and Amazfit before purchasing. Do not rely on marketing headlines alone.

For athletes: who wins?

Running (road and track): Amazfit Cheetah 2 Ultra. Verified HR accuracy in hot, intense conditions and the SmO2 sensor for effort monitoring give it a real edge for runners focused on performance metrics at a much lower price.
Trail and adventure: Garmin Fenix 8 Pro. The mature ecosystem, established GPS reliability in challenging terrain, rugged build, and LTE option make it the safer choice for remote or technical environments.
Triathlon: Garmin Fenix 8 Pro. The breadth of multisport modes, third-party app support, and training load tools across disciplines give it an advantage that Amazfit has not yet matched at the system level.
Recovery tracking: Amazfit Cheetah 2 Ultra. The SmO2 sensor adds a layer of physiological data unavailable on the Fenix 8 Pro. Combined with strong HR accuracy, it offers more granular recovery insight for the price.

Verdict

For most runners and hybrid athletes, the Amazfit Cheetah 2 Ultra is the smarter buy. It delivers verified biometric accuracy, a unique SmO2 sensor, and capable multi-band GPS at roughly half the price of the Fenix 8 Pro. The Garmin Fenix 8 Pro justifies its $1,000 price only if you genuinely need LTE, a deep third-party app ecosystem, or the specific demands of expedition and adventure use. Buy the Fenix 8 Pro if you are a trail runner, alpinist, or triathlete who relies on the full Garmin platform. Buy the Cheetah 2 Ultra if your focus is running performance and biometric depth at a realistic price.