I think cold start times on modern GPS units are on the order of 30 seconds now. Even if you lose all almanac and ephemeris data, and don't know what time it i

I think cold start times on modern GPS units are on the order of 30 seconds now. Even if you lose all almanac and ephemeris data, and don't know what time it is. AGPS is nice (2s cold start times), but by no means essential for a decent user experience. (The datasheets are not a lie. I have had a ZED-F9P on the shelf for a month or so. Plugged it in and had a fix in 32 seconds. The delay was that I could only see 3 GPS satellites, so had to fall back to the slightly slower multi-constellation warm start.)