You realize that Mazda does the same thing, right? It just has the ability to send 50% of the available torque to the back axles to do that same thing with, as well. It's not a real AWD like a Jeep/Audi/Subaru/etc.
My sister has a Jeep Cherokee and it completely disconnects the rear axle most of the time and is FWD. Subaru if it has a CVT is similar to our setup (the WRX and STi are exceptions). As are Audi’s with Haldex. Very few vehicles will have what you’re talking about and probably need for your situation.
I still believe Mazda’s setup is one of the better ones and it worked very well recently when I was as driving in ice. There was a Jeep behind me struggling more. I suspect he didn’t have winter tires like I do though.