Solid and keeps it's zero. this is the sleeper deal of the year - ADE Advanced Optics NUWA Micro Red Dot Sight

ADE has a reputation for making budget optics, but this seems to be their first foray into a higher end optic designed for a carry gun. They seem to be marketing toward the RMSc footprint, lightweight carry pistols such as the Canik TP9 and Sig P365. I personally have it on a Glock 43.
The construction is solid with a coated glass lens and aluminum body. I've dropped it a couple of times, and not only is it fine afterward, the zero was unaffected. Zeroing it was pretty easy as it went on the slide pretty dead on, so your experience may not be as easy as mine. Zeroing is done with a standard flathead jewelers screwdriver. It co-witnesses about 75% with my existing standard height Truglo sights, unlike the Swampfox Sentinel, which I consider to be the closest in feature set to the Nuwa which needs suppressor height sights for co-witness. It dropped onto the RMSc slot on my Glock very snugly. I used a couple drops of blue LocTite and it doesn't appear to have budged since, and I grab the optic to rack the slide a lot.
The dot is 4 MOA, which is a little big for precision shooting, but is (at least for my failing eyesight) easy to pick up and find. I'd have preferred a 2.5 or a 3 MOA, but this is personal preference. Being as this is meant for a carry gun; the larger dot is probably preferable for quicker target acquisition. The always on feature is also better on a carry gun and is normally a feature of a much more expensive red dot. The automatic brightness feature works well as per my eyes. In very dark conditions the dot can get a little dim, but this is by design to not wash out the reticle; again, a feature ideal in a carry optic because if it's that dark you can't be sure of your target and what's beyond it. Brightness changes are instantaneous.
The dot itself is crisp and bright. It was easily visible in bright daylight or evening conditions. From what I understand this can vary from person to person if they have astigmatism, but this applies to all red dots.
Criticisms are mostly related to the design and fit and finish. The zeroing screws don't appear to be of the highest quality. Although they seemed to hold up when I zeroed it, they looked like they might be easy to strip out. The housing is a little on the ugly side. I'm guessing the texture they put on the sides was to aid gripping the optic if you're using it to cycle the action, but I didn't feel like it helped much and only took away from a smooth look for the optic. With that said, function is far more important than form.
I'd say it was an easy competitor to the Swampfox Sentinel Auto that it shares a feature set with but manages to come in at about half its price. The Swampfox is supposed to have a superior emitter, but I haven’t had any issues with visibility or flickering this one. The ability to co-witness with standard iron sights was a major factor in having chosen this over the Sentinel.
I really can't speak as to battery life being as I've only had this for a few months, but having to take it off to replace the battery is a bit of a pain, but is common to this class of red dot sight. I did have to remove it once and it retained zero when I remounted it.
This is a sleeper value. I'd highly suggest getting one while they're still relatively not well known about and still affordable.