[amsat-bb] Gold Standard for Keplerian Data

I have noticed that when I update the Keplerian Data for my location on SatPC32 and generate a list of passes they all seem to be about 5 minutes different than the predictions from the AMSAT website. This is for the earliest pass, and I am using the exact GPS coordinates for my location.

So which do I rely on? Which predictions should I consider the "gold standard" for passes?

Steve, W5IEM