It depends on how much area you need to cover.
But here's a little extra info to help you decide:
One Wyze Mesh Router System (2-Pack) can cover up to 3,000 square feet while a Wyze Mesh Router Pro System (2-Pack) can cover up to 4,000 square feet.
Each individual Wyze Mesh Router and Wyze Mesh Router Pro covers up to 1,500 sq. ft. and 2,000 sq. ft., respectively. See: Router Comparison Charts | Coverage-and-Capacity.
You can have up to 10 mesh routers on one network, with no more than 2 hops from the root router.