Thanks for all the replies and the specific suggestions. I like having some choices to consider other than the Zebralight as they are pricey, but I'm wiling to spend that much if that is what it takes. I think I will likely find some other uses for a good headlamp anyway so that justifies the cost.
I'm going to research and compare the different options presented. If generous return options are available, I may narrow it down to 2 and order both to compare 1st hand.
Tachead, were the Olight or the Manker AA among the models that you tried and you prefer the Zebralight?
I also have a question re the Zebralight. I believe that I read that the moonlight mode can be programmed. Does this mean that you can set moonlight to, say, a little brighter than the factory preset and then quickly access it every time you turn the light on?
Zebralight lights are expensive for a reason. They have more advanced and efficient drivers, better quality aluminum, much tougher anodizing, and are lighter and smaller then most, if not all, comparable lights on the market. Their electronics are also fully potted for durability and their bodies are made from a single piece of Alcoa aircraft aluminum for added strength and better heat transfer and dissipation.
Zebralight offers a 30 day money back guarantee. So, if you don't like it for any reason, you can send it back for a refund and will only be out a little bit of postage.
I haven't tried the particular Olight headlamp referenced but, own another model headlamp that uses the same type of honeycomb optic. It produces a nice beam that is fairly smooth and I rate it's beam as the second best option after the mule(bare emitter) style. The Zebralight frosted lens comes in at a close third. But, you should keep in mind that Olight is a step down in quality compared to Zebralight and is not offered in as warm of a CCT. Their neutral white models are generally 5000K nominal which is much harder on the eyes late at night and will cause more glare/reflection. They are also much lower in CRI then certain ZL options like the "c&d" models and don't offer a moonlight mode.
As for the Manker, it is a standard reflector based headlamp which produces the worst type of beam profile for reading imo. It will have a defined hotspot which most don't like for up close tasks like reading. Manker is also a "budget" light brand and while descent quality are nowhere near the quality of a Zebralight or Olight.
Yes, Zebralight offers three different true sublumen moonlight modes to choose from. You can set which you like most and then the light will come on in that mode. You can then double click at any time to step up to the normal low mode(2 lumens on the H502c).
So, when it comes to Zebralight, the two models I recommend are the H502c L2 and H53Fc for reading. They both are a nice warm 4000K and are very small and light.
The H502c has the best beam for reading imo because it is pretty much perfectly even across the whole beam. But, it has a wider spill which has more chance of hitting your wife. I don't think this will be a problem though as you can run it at a very low output. It doesn't bother my spouse at all. It's spill also abruptly ends and you can adjust its position so your wife is not in it's spill.
The H53Fc is a newer model with slightly higher CRI and efficiency but, is a bit larger. It still offers a nice beam for reading but, is not quite as even and requires that you point it at the page you are reading more carefully. It also causes a slight bit more glare/reflection due to its tighter beam but, it still works pretty well. It offers a bit tighter spill that transitions smoothly to darkness.
Sorry, that was a bit long winded. I hope it helps.