I participated in a Neo T3 passaround, and it's a fun little light. Damn bright too. Its runtime might appear to be short, especially if you expect to take long walks at night with it, but in the 2 weeks I had it, playing around with it both indoors and out, for a few minuetes at a time, I never drained the SF battery I stuck in it. So it'd be just fine in a purse or by the back door for quick tasks.
However, I myself won't be buying one. There's a few reasons for this, and coincidentally (or perhaps not), it's because my Fire-Fly III beats it out for each reason.
1. Size. Yes, it's a small light, but the FF3 is smaller. Obviously this is because of the comparitivly gigantic reflector of the T3, but despite the smaller reflector, output/throw with the FF3 matches (or beats--barely--on burst mode) the T3. Reportedly the McR 20 reflector is a perfect drop-in in the T3, and improves throw. If I win the passaround raffle, it's getting a new reflector.
2. No rechargables. This is the biggest killer for me. Not only is it not reccomended since you'd fry the light, it's impossible; they don't even fit. A pocket rocket with this kind of Wow Factor begs to be used, and given the runtime, this could be an expensive light to run if you expect to use it daily (er, nightly).
3. No low mode. As more and more new lights come out, the less interest I have in lights without at least 2 output levels. IMO, except perhaps to keep costs down, there's no excuse anymore for single level lights. But IMO, multi-level output more than justifies the cost, since you're getting a more useful light. For example, if you have 2 different lights, one with low output but long runtime, and one with high output but short runtime, and they both cost $50, you're better off buying a $100 light with 2 output levels. And since both modes are combined in the same light (making it more useful), you're getting more than twice the flashlight than either single-level lights.
Which is why I prefer the Fire-Fly III over the Neo T3. I've got 3 output levels, including a low mode that quite often is all I need. WIth the T3 you're stuck with a rather bright light, which might be way too much.
Still, the Neo T3 is a very well made light. Regulation is pretty good; the gradual dimming is pretty much unnoticable by the eye unless you compare it side by side with one with a battery. The anodization is extremely hard (and almost feels like it's teflon coated--you're not going to scratch this light). The threads are like greased butter.
But unless you're unwilling to pay the extra cost, the Fire-Fly III is a superior light all around.