As an experiment, I took my old BIP out of the drawer it has been in for the past couple of years. (It was replaced by a Stratos) It wouldn't start as the battery was dead so it went on charge for 15 minutes. Zepp has been removed from my phone so there was no AGPS available, which I recall was available with the BIP. From cold it achieved a lock in 33 seconds in a reasonably clear location. In that same location the Huawei GT2 takes between 5 and 8 seconds to achieve lock.
The BIP produced more accurate tracks than did the GTR, but neither gets near the GT2. I am amazed that, with all the evidence from the GTR, Amazfit continue, as reported here, to produce devices with what is effectively a non-functioning GPS.