The MSI MAG X870 TOMAHAWK WIFI wins in 4 out of 14 comparable specs, with 8 ties. Its biggest advantage is USB Type-C (100% better).
B850 GAMING X wins in 2 specs (PCIe x1 Slots: 100% better).
Recommendation
Choose MAG X870 TOMAHAWK WIFI if you want the best overall performance — especially usb type-c.
Choose B850 GAMING X if pcie x1 slots matters more to you.
