@Joe-c,
It will certainly be interesting to see images produced by the two cameras in a side by side comparison.
Sadly the number of owners of the new FLIR ONE present on this forum appears limited at the moment. I am awaiting delivery of my Android version of due at the end of this month or early August. Once it is released we should see more sample images here. For distance work, it is usual to specify detection of a human adult. In the thermal domain that is often detection of hands and face as clothes will reduce the thermal signature somewhat. Ambient temperature is also a factor that needs to be considered as that provides the thermal contrast.
In the hunting scenario, the target is a very different to a human adult in terms of size and heat distribution.
It would be helpful to know the scenario in which your friend intends to use the thermal camera as this will influence the test. I am the guardian of three cats, but achieving a 100m observation of them is not possible as they are house cats. I may be able to do some 'spotting' of neighbours cats at such ranges though. A cat is actually a pretty tough target for a 'simple' thermal camera at range. They are well insulated and the hot spots are normally limited to eyes, ears, nose, mouth, and paw pads. All are quite small compared to pixel size at long range. On the positive side, they are similar to some hunting targets in terms of thermal signature and they are common so someone with a SEEK could also produce such images for comparison.
Aurora