Pros:

Polygon currently has two scaling solutions live today – 1) a PoS chain with lower security guarantees and 2) a Plasma bridge with higher security guarantees. Their Plasma solution can be considered a true “Layer 2”.
Polygon now secures ~$3.5B in total value split across their PoS chain (~$3.1B) and Plasma (~$400M). Most of the growth has happened over the past month, driven by a high gas fee environment on Ethereum. Polygon’s EVM-compatible solutions have made it easy for existing dApps to migrate over while projects like Connext have helped facilitate cross-chain liquidity inflows.
A robust ecosystem has quickly formed on Polygon, led by blue chips such as Aave, Sushi and Curve, to name a few. A strong business development team, a new $100m ecosystem fund and an active community are helping to further spur ecosystem growth and integrations.
While estimates vary on throughput potential, Polygon’s PoS chain was able to reach 7,200 TPS on testnet with 100 validators. On mainnet, we’ve seen instances of 300+ TPS but we’d need more stress testing for a better figure. This is an impressive amount of scalability at that level of decentralization. For context, Ethereum can facilitate ~15 TPS. The team also confirmed that Plasma has the same level of throughput.
The development team is taking a generalized approach to scaling, looking to offer several L2 solutions rather than focusing on a single one. The roadmap includes added support for ZK-Rollups, Optimistic Rollups, Validium Chains and more Sidechains. The end goal is to become a “L2 aggregator”, putting it in a unique position which stands to benefit greatly from the vast ecosystem already growing on it.
Polygon SDK is coming soon, which is a modular framework that will allow for the easy creation of standalone, EVM-compatible chains. Polygon’s team has already been doing PoCs with several enterprises. Polygon SDK will be somewhat similar to Cosmos SDK and Polkadot’s Substrate but based upon the thesis that the multi-chain world will be built as an extension of Ethereum.

Cons:

99.8% of the value secured in its Plasma solution is derived from MATIC tokens, which the development team likely holds a significant portion of. This demonstrates that Plasma, despite being a live layer 2, has yet to see meaningful uptake by the market. This may be due to obstacles related to asset mapping or an unwillingness to deal with 7 day waits on withdrawals back to Ethereum.
Polygon’s PoS chain has worse security than rollup solutions given its reliance on an external validator set. We’d like to see greater growth in the amount of MATIC staked to counteract this since only 15% of the total supply is currently staked. However, growth here has been slow in light of higher yielding opportunities elsewhere. The PoS TVL / Staked Matic Ratio, which helps measure the attractiveness of an attack, is currently ~3.1x. This ratio will be important to keep an eye on moving forward.
The PoS chain has a meaningful level of validator centralization with Binance accounting for 37% of staked supply. The top 10 validators make up 81% of staked supply.
Withdrawal times are 1 hour for PoS and 7 days for Plasma. The latter is in line with withdraw times for Optimistic Rollups but much longer than for ZK Rollups and may hurt UX relatively speaking.
The commitchain pays gas fees on L1 from the Polygon foundation treasury. This reduces user friction, which is key to the team’s goal of further increasing adoption, but requires a better long term solution.
While the L2 aggregator strategy has promise, there is execution risk delivering the various solutions to market in a timely manner, especially given the specialized teams (i.e. Arbitrum, Starkware, etc.) going live first. It remains to be seen whether Polygon will build their rollups in-house or plug into external solutions.
A past concern was the upgradable proxy to the bridge contract controlled by a 2-of-3 Gnosis Multisig, which would hav