The physical installation of the switch was extremely easy and required nothing out of the ordinary as compared to connecting a typical switch. I simply removed the "dumb" primary switch from my 4-way circuit and wired in the ZOOZ Zen26 in exactly the same manner as the switch that was removed. This took all of about 10 minutes. If I had to replace all four switches on the circuit, we would have probably be closer to 40 minutes.
The only downside I experienced with the ZOOZ Zen26 reared its head at this point, as while handling it for the installation I determined that the build quality wasn't quite as high as the switch being removed, or as the GE/Jasco switches I already have installed. It felt a little less substantial, and of concern was that when I inserted the ground wire there was not stop in the hole, and the wire was able to go all the way in so that it could push the Decora style rocker cover out. I have installed plenty of switches before, dumb and smart, and I have never experienced this. The cover of the switch, the top side that you would press to turn the light on, was pushed out far enough that I could see the ground wire behind it. So, I had to pull the ground wire back while toggling the switch to make sure it was back far enough to prevent interference with the operation of the switch. In the end, perhaps not a huge deal, but it contributed to my sense that the switch build quality wasn't the best.
The physical installation was a snap, and so was pairing the switch to SmartThings. The pairing process is straightforward, and within a minute or two the switch was available in the SmartThing's app and I was able to customize it to my liking. The three screenshots below show the tabs of the device's entry in the app, where you can see it looks much like any other switch within SmartThings.
One thing not shown in the screenshots above is the option to configure the blue LED light found on the face of the switch, which is mainly due to the default device handler it chose when installed. Changing the handler type would reveal the configuration of the LED, but since it is set to my preferred configuration - to have the blue LED on when the lights are turned off - I left it alone. When actuating the circuit from the app, the Zen26 switch, or from the 3 dumb switches on the circuit, everything works exactly as expected. The ceiling lights can be turned on and off reliably, the blue LED always changes state properly, and the app is quick to indicate the change in state. I couldn't ask for anything more.