Starting with the most recent and going backwards in time:

Sivyh: Exploration: 20450, Observation: 19250
Denawe: Exploration: 15820, Observation: 17980
Ageryn: Exploration: 16425, Observation: (not yet included in PBF)
Sulye: Exploration: 12450, Observation: (not yet included in PBF)
Kasir: Exploration: 17350, Observation: (not yet included in PBF)

I feel like these are pretty low compared to some people, especially given the # of hours all those (except Denawe) had.