Good luck with the Eiger.
I tried to make the Peaks work for me but in the end gave up. A combination of difficult websites, unresponsive (to email queries) staff, and hard to assess product did not help.
Also, certain information holes could not be filled.
E.g., if you wanted the Eiger in Titanium, you'd find you could not in fact key chain it! A big defect for a "keychain" light. Since you couldn't get the lug attachment in titanium and the websites would not tell you whether you could substitute another lug attachment material successfully.
I tried to give the Peaks more than a fair shot, including building an elaborate spreadsheet to track the brightness/runtime information thrown about here and there in the websites, and adding conversion factors to project higher power and to convert the foot candelas to something more meaningful. I tried to analyze the data to understand runtimes better (since the data Peak gives you is in a rather hard to use form). Etc., etc.
When you think about the materials that Peak provides, it turns out titanium is problematic (only available for the Eiger, without a lug attachment). Getting the 2xAAA (or 2xAA for the El Capitan model) battery tubes, obviously very important for a light that is not electrically regulated, is not possible for many types of metal offerings. Again, the websites are not helpful to explain what is going on here -- is it the case that all materials will get the 2x battery tubes, or not?
The Aluminium (HA) model is pretty ugly, and the SS and brass models are too heavy (and I wonder how heavy in the 2x battery versions!). I checked the tensile strength properties of the various metals and brass does rather badly actually. So if you buy the "prettiest" material (clearly, brass) you then get something quite a bit weaker than you are used to in terms of strength.
Then the lack of electrical regulation is an issue, these lights are direct drive but after you follow the specs (the spreadsheet I mentioned above, with plenty of time consuming data entry and analysis) it is not obvious that you get higher efficiency relative to the regulated competitor models (like you should).
In the end, you can get a simple regulated 1xAAA or 1xAA light that can do more than the Peaks can.