Depends on the insert and router attachment design. Mine's a Jessem and the router is clamped within the lift. It's far sturdier than a plate alone.
If you're not contemplating a lift and, have a smaller router, using the router plate would be fine. Probably be easier to change bits, too.
If you're not contemplating a lift and, have a smaller router, using the router plate would be fine. Probably be easier to change bits, too.