" ... 2. It seems favorites lists are of little value in "GPS mode". Is it best to simply turn on the entire database and use service types to limit what I hear?... "
I don't travel much now, but I had my HP-1 for a couple of good travel years. I live in Phoenix, AZ. While waiting about three days for delivery of the scanner, I downloaded the Sentinel Software and constructed FLs for my home base area and also for some familiar travel routes.
I named the "travel" FLs for the Interstates involved: Phoenix-LA = "I-10", Phoenix-San Diego = "i-10/I-8", San Diego to Las Vegas = "I-15", and Las Vegas to Phoenix = "I-515/ I-93/ I-60".
Using Google maps for place names (towns, cities, airports, Counties, etc., I soon could make a State crossing FL in about an hour. I pretended to live at every point along the route and I would "append" to the FL those entities (and ONLY those entities) that I would actually listen to if I really did live at any given location along the route.
With the GPS in operation, I could travel from Phoenix to San Diego,then to LA, then to LV, and then back home to Phoenix, while scanning EXACTLY what I would be scanning if I lived at the location of my moving vehicle. The TGs and Channels come and go without the need to touch the radio. It was actually quite mind-boggling to experience the effect.
As to the "Entire DB"? I, personally, have never had a use for it, anywhere, anytime. In Sentinel, the FLs are constructed from the DB, but if the DB was not even in my scanners, I would have never known it.