Hi, thanks for the report. I’d like to break this down into two parts.
First, you mentioned that the value of GetNetworkPing() does not correspond to the ping shown in the network debug pane opened with Shift + F3. These ping values actually represent slightly different concepts. The value in GetNetworkPing() is the network latency of individual packets between your computer and the Roblox server, while the ping in the network debug pane should include this value plus latency from the packet deserialization/processing pipeline in the Engine.
The value from GetNetworkPing() should generally be lower than the one in the network pane, but the Engine uses different algorithms to calculate the running average of each ping, which may also cause differences. Do you regularly see GetNetworkPing higher than the ping in the network pane like in your screenshot?
Second, you mention that some players have pings higher than you expect, while others have pings lower than you expect. Can you clarify what baseline value this is in reference to?