I see pros and cons to this system. It's not for everyone but I think it will have some value in niche markets and applications.
Battery and Motor technology has come a long way in recent years. I can remember in our shop the only way to take tires off of our trucks & tractors was with air impact wrenches. The thought of a cordless impact wrench was a just a dream. Now today, the air impact tools rarely get used and the cordless impacts get used everyday.
I do agree, I'm not a fan of batteries dying while operating my layout and having to charge batteries in trains. Not to mention I really hated replacing batteries in my Lionel & MTH engines and was very happy when battery replacements (Super Capacitors) were introduced as an alternative. So in one way, this system is a step backward in this regard.
When I think about everything on my layout that needs power to operate, the track wiring becomes a small piece of the puzzle in the grand scheme of things. Accessories, track side operations, multiple buildings, & switches still need wiring.
Another concern is cheap batteries and cheap chargers. I've personally seen quality lithium laptop batteries self destruct and do considerable damage to the laptop and furniture it was on while charging. I would never charge these batteries unattended and even then, rechargeable lithium batteries can be dangerous while in use (Samsung Galaxy Note 7). My dad's cell phone burned a hole in his jeans because of a battery failure.
I do like the idea of portable indoor and outdoor layouts that don't need any wiring. This would be so simple to set and tear down. Not mention you can run in environments where an outlet is not readily available.
For me, I like my smoke units and full feature sound coming from the loco. The idea of waiting for batteries to charge, wondering how much charge is left or if a battery is still healthy kind of takes the fun out running my trains. And as I said earlier, maintaining and replacing batteries was something I was happy to get away from.
But just because this system doesn't suite me doesn't mean it should just go away. I'd still like to see this technology receive further development. It may fit the bill for others and how they like to operate trains!
