I've bought XOSS G+ bike computer https://xoss.co/ru/products/xoss-g-gps-bike-computer?variant=31355022442631 with speed and cadence sensors and enjoyed my rides with such configuration
After I bought Forerunner 955 I connected these sensors to it leaving XOSS G+ working on the bike. And noticed that distance is always more by ~10% on Garmin. The wheel size is the same on both
The question is - does Forerunner 955 calculate distance using speed sensor and prefer it over GPS?