I can’t answer this question. And I don’t want to answer because it would be definitely wrong in some situations.
But you should take care of some aspects:
- What is the delay ( RTT ) to the remote server
- What is the jitter to this server
- Is this just a snapshot or is this a long term average.
I am running three stratum 1 server ( DCF77, GPS and atomic rubidium based )
As reference I use BEV ( Bundesamt fuer Eich und Vermessungswesen ). This is a government in Austria and official responsible for time. They offer three stratum 1 server. If I do a 10 day average compare between my GPS based server and BEV I see sometimes a positive drift using a calculation with a polynomial of first degree but a negative drift using a calculation with a polynomial of second degree.
So what should I trust in this 10 day period ? But over long time they identical in a certain range.