Review on 📞 Highly Efficient Grandstream GXW4104 4-port FXO Gateway for Streamlined Connectivity by Bart Schwalbe

Works well. The setup wasn't that intuitive and the documentation doesn't help much. You really need to know something about configuring SIP to make it work. It doesn't work very well as a standalone device, it's best set up with a SIP server, i.e. H. Asterisk. It works directly with a SIP phone if you only have one phone per line. If you need multiple phones per line, conference, etc., you need a SIP server. I've been using it for a few months now and it works consistently.