I need to revisit my combo of documentation & testing as it has got quite old and we now have the much better L2C signal to receive. My first Garmin used to take many minutes to do a warm fix and when I used it in the States in 2006 it took well over an hour to get enough satellites before it became vaguely useable.
Testing a NEO-6M based module recently in the office, downloading assist data via the u-Blox software certainly kick started each one but I wasn’t paying much attention to the details - finding a position in the rafters to put an antenna so I didn’t have to string multiple SMA to SMA cables to get one outside was taking up my attention. But it was clear from a brief test between rain that the most beneficial thing was an active antenna outside with a 45° cone of visible sky, second best was the same active antenna in the rafters but away from other cables / flourescent tubes etc.
Most of the personal trackers are pendant based with a ceramic block antenna - I don’t know how that particularly differs from one of the mag-mount active units but I bet being sideways to the sky doesn’t help. But I do know a NEO-M8N with ceramic block wasn’t picking up anything when put in the same place as the active antenna.
I’ve a box of NEO-6M’s which I think would represent a typical entry level GNSS module that have never been used, maybe I can figure out a test setup and try things out - included the all important current consumption.