If you save both 2.4 & 5G the phone will always (or, almost always) default to 5G if the signal strength is adequate. This is because 5G will normally have faster connection & throughput even though, the signal strength is less. I've confirmed this many times with repetitive, back-to-back speed test using a variety of servers. Sometimes the differences are small, sometimes substantial but overall 5G wins. I used to keep mine on 2.4 for the extra range but no longer bother. My Asus AC68U has 5G range sufficient for my home interior & grounds so I just let the device select now & couldn't be more satisfied. The Turbo actually equals 2, ethernet connected desktop computers & that speaks volumes about the hardware capability. Also, to date every Turbo I've seen with WiFi issues could be traced to the router - old & outdated lacking modern protocols or badly in need of a firmware update or both. Saddle these bad boys up to a good network & watch it fly.