IOT Security HW: Useful or not?

Been seeing adds for more things like this lately. While I use a PC based router, I really need to move away from that; life commitments just don't give that luxury anymore. Been seeing more widgets like this to help secure the "modern home". Do these actually "work" or is it just a cash grab based upon FUD?

https://homealarmreport.com/cujo-dojo-vs-keezel/

As a security professional by trade I can tell you that an IoT device to protect your IoT devices is a waste of time/money. From a practical perspective the best things you can do that are low maintenance are:

1. Setup a second VLAN on your Firewall and have all of your IOT things connect to that network. Block all outbound ports except the ones as documented on their respective websites. <-- Yes this could take some effort, but its a one-time deal per device type. I haven't touched my rules in almost a year.
2. Use your Firewall to Restrict Outbound DNS to a "trusted" server. I use OpenDNS.

Most Malware, etc. has to call home. These two things stop most of it.