I bought one of the originals a couple of years ago when they came out. I ended up not using them because they were worse than irons, IMHO, in low light. With a tritium light source, maybe they fixed that.
Anyway, here's my 2 cents (bearing in mind that I haven't seen the new ones; am just assuming that tritium would make them work as well in dim light as the originals do in bright light):
Pro: No batteries to run down, no electronics to fail!
Con: Haven't drop tested, but doubt the exposed half lens would fare well if dropped on a piece of gravel or some such. Tritium dims eventually.
Con: has some parallax. Someone upthread suggested they have a short sight radius. That's not how they work - they present a triangle floating out there like a reticle. My sense is that parallax is worse than red dots, though not enough to matter inside the house.
Con: my sense is that they are worse about obscuring the target than conventional irons (pistol or rifle) or the mini red dots (Bushnell TRS-25, Aimpoint T-1, etc). I just mounted the Seeall and compared with conventional AR irons and a mini red dot for a scenario wher you want to watch a burglars hands. The A2 irons are narrow enough you can see on wither side of the sight tower, and of course the red dot is transparent. The Seall is tall, wide, and opaque. It's not a show stopper, but it's noticeable.
Overall, it's a cool idea, but for the price (especially of the tritium version) I'd rather have a dot. YMMV.
