QCA9561 Vs MT7621AT

Avoid the Asus RT-ac58u like the plague (not enough RAM, 128 MB is not sufficient for a dual-ath10k device).

Linksys tries to hide the hardware revision from the buyer as much as possible, it is marked on the back of the device (model/ FCC ID) - if you're lucky also on the lower of the three barcodes on the small lower edge of the packaging (but this is not always there).