It's allready been said but there is really no ONE best light - however this is my recommendations.
I own the following 123 lights: Novatac 120T(P), Eagletac D25C, SWM V11r, Jetbeam RRT0, HDS Twisty and HDS Clicky. They are all excellent built and appears to be of good quality. I have not had trouble with any of them, and I am not afraid of dropping either of them in the concrete if so should happen (knock on wood it doesn't). All of them gives enough light for my day-to-day purposes, even though their lumen ratings differ from 85 on the HDS Twisty to around 500 on the ET and SWM (with rechargeables). As I see it all new lights give out enough light, and they all have decent run times on lower modes since the LEDs are getting incredible effective these days. If I were to buy a new 123 light now I would start with the following considerations:
UI:
I have found that for my needs nothing comes close to HDS when it comes to User Interface. To programmable levels at hands from off, and two more just a few clicks away is great. I also love that you can turn on / off both momentary, button lock and last mode memory among other things - this flexibility is great. It does however make the lights more complicated and several of my friends prefer either the 4seven tactical UI or the adjustable control ring of the SWM.
So if I where to choose a new light I would start with which UI I think would suit me best.
Tint:
Almost all vendors produce their lights with almost the same LEDs so you should be able to find the tint you like almost independent of which UI you like (and if not there are several people here who can help you). Personally I like the warmer lights with more yellow then blue, but this is a personal preference. I find it easier on my eyes, and especially if I am looking for something beneath a couch or something I find that cool lights sometimes doesn't help as much as warmer lights. So I would recommend something a little warmer.
Material:
The same goes for material as for LEDs, you can have almost any light in both HA and at least Titanium. I only have one Ti light (the ET), but I wish they all where. I reccomend that you buy a Titanium light. It is lighter and the small dings you will get if you actually use your lights doesn't ruin the appearance as much as dings on anodized aluminum.
My dreamlight (and hence my recommendation) would be a Titanium HDS Rotary High CRI, and if there are no Titanium made I would recommend finding a normal one (buy used if you want the light now and not within a year or so).
Allthough price is not everything I think you normally get what you pay for. In this I mean that a pricier light gives you another feeling then a cheaper light, although they probably do their task (which is producing light, not being locked away in a safe) more or less equally good. I dream of a McGizmo although I can't justify it to my wife :tsk:
Since you want the best light you are probably wanting to look into the higher ends of flashlights, but if not I think you should start with how you will use the light and what UI that is best for you. That may not be a McGizmo...