Here are my first impressions on the ThruNite Ti:

Shipping was very quick. The lights were well-packed and arrived in good order. I would definitely buy again from Illumination Supply (note: I was given no consideration for my review, and I have no affiliation with Illumination Supply or ThruNite other than as a customer).

The flashlight came with a manual, two spare o-rings, and a sturdy-looking split ring, perhaps slightly larger than I would have expected for a keychain light.

The flashlight itself has a very high build quality. Anodization is impeccable, and the lettering (including serial number) is razor-sharp. A special note on the knurling, which is generous and well-cut. ThruNite seems to have found the perfect way to cut knurling such as to make the light easy to grip without being rough on your fingers or catching on things in your pocket.

It's easy to operate one-handed. While I haven't had it very long and I don't know how it will stand up to keychain carry, the first impression is that ThruNite paid very close attention to details and quality control.

There is no pocket clip and the light will roll off a table easily. The keyring attachment is sturdy without being bulky, and a flat machined on the end allows the light to tail-stand.

The UI is simple: Twist on for firefly (ultra-low) mode, and twist on tighter for high. It's easy to accidentally skip firefly mode, which if you're working in the dark can lead to ruined night vision before you back off and find the sweet-spot. My rough measurement is that there are about three millimeters worth of firefly mode. Give this light to a non-flashaholic and they're almost sure to think it's a single-mode light.

The mode spacing is less than ideal. Firefly mode is useful only in total darkness and very low-light conditions, where high is good and bright for a 1xAAA flashlight. A low mode in between firefly and high would be really good to have, although that might be tough to do without significant additional expense.

Beam quality is excellent, with a tight hotspot and good spill. No artifacts seen. Tint is a bit green.

Compared to a Fenix E01, it's much brighter on high and runs much longer on low, with a better beam quality and much better tint. The E01's single mode is much more useful (to me, at least) in moderately low-light conditions.

Compared to a 4Sevens Preon ReVO, the ReVO's low mode is more useful and the high mode is noticably higher. The ReVO is thinner and has a better tint too. But the ReVO is almost three times more expensive and discontinued to boot.

Compared to a Titanium Innovations Illuminati, the Illuminati has a useful pocket clip, better tint, better mode spacing and the best beam I've ever seen in a 1xAAA flashlight. But it's nearly as expensive as the ReVO and harder to operate one-handed.

The best comparison is to your particular flashlight needs. If you need a single AAA keyring flashlight with a very low low and an excellent high, the ThruNite Ti can't be beat anywhere near it's price range. I like it a lot.