Pros and Cons of PoS

Advantages

• Validators don’t need expensive specialized equipment to set up nodes, a standard computer will do thus encouraging decentralization.

• PoS protocols are highly energy-efficient & sustainable because validators do not need to solve resource-intensive puzzles.

Disadvantages

• Validators with the largest amounts of staked assets or multiple pools have significant influence in validating transactions, which could pose security risks.

• PoS systems with a small number of active validators or those that overly rely on centrally hosted Cloud services (vs bare metal, self-hosted nodes) reduce decentralization.

Disadvantages that do not apply to cardano

• Validators on some PoS consensus mechanisms must lock up a small amount of their assets (pledge), which can’t be unstaked for a set period.

• With some chains, delegators and validators can risk losing part of their staked funds (slashing) if validators validate inaccurate transactions, go offline along with other validators, or attack the network.

Source: https://www.essentialcardano.io/article/6-types-of-blockchain-consensus-mechanisms