I'm always interested in new protective products. Just quickly scanned the website for this Breath of Life mask. From what little I've read, this seems more like what I'd call a general purpose "escape mask". There's nothing wrong with that, if you keep its limitations in mind.

It will filter a lot of acrid stuff in smoke, but apparently not carbon monoxide, so that makes it not a great smoke hood, if that's a big thing you're worried about. There's also no mention that the hood itself is heat resistant. I'd hate to have this hood "shrink wrap" itself onto your head when exposed to a burst of high temp air.

Although it does filter various chemicals and biologicals, it doesn't seem to really be designed as NBC protection so it's not necessarily great at that either. It only has a 1.2 mm activated charcoal layer. I'm not familiar with the materials in the other layers.

It seems to be an OK product. No better, no worse than many other "escape masks" out there. From what I've seen, you generally need to purchase both a smoke hood and a separate NBC mask to get decent respiratory protection against both situations (putting aside the issue of protecting the rest of your body).

I personally wouldn't bother with NBC. The biological/chemical threat at least really requires you to be aware of the problem before it happens. Take the sarin attack in the Tokyo subway. I have to wonder if it really would've changed the outcome at all for those riders if they all had masks on them? I doubt it. For one thing, no one is going to have the foggiest clue what is going on even while people are dropping like flies so I think pretty much 100% of the people still would still have been exposed even if they had the masks.

If the authorities are making an announcement on the PA system about a chemical/biological attack, then you know the agent was already released a while ago and if you haven't dropped dead already or been infected already, you're probably in minimal danger where you are, so again, there's not much use for an NBC mask.

From my own experience living in NYC, I'd probably pick a decent smoke hood and keep a decently bright flashlight as far as preparing for a likely "quick escape" scenario, whether from a structure or subway fire. I think fire is a threat that has a decent chance of being experienced by many folks and often provides enough lead time to actually don the mask in time to have it help.