Which 5GHz band is best?

Best 5GHz Wi-Fi Channel

WiFi network speed— The higher frequency 5 GHz band makes up for its shorter range with much faster WiFi speeds than the 2.4 GHz band. To compare, the 2.4 GHz band will support speeds between 450 Mbps and 600 Mbps, while 5 GHz will support speeds of up to 1300 Mbps.1 Nis 2019

Simultaneous dual-band routers are capable of receiving and transmitting on both 2.4 GHz and 5 GHz frequencies at the same time . This provides two independent and dedicated networks which allows more flexibility and bandwidth.