Explorer Limitations:  Alas, the inability to view local hardhat node transitions in detail! The absence of an explorer to observe the transitions made on the local hardhat node poses challenges when debugging failed transactions.

Account Impersonation:  Public Testnets are designed to not allow anyone to impersonate other accounts, thus limiting the testing possibilities and hindering comprehensive testing.

Public Testnets,  a potential time sink! Public Testnets are not designed for quick transaction processing. In fact, transactions on these networks can often take as long as 13.5 seconds to complete. This can be a major inconvenience during contract testing.

Token Scarcity:  Acquiring a sufficient quantity of Testnet tokens for comprehensive testing proves to be a time-consuming Task.

BuildBear Faucet: Through the BuildBear Faucet, Prof. Fábio Santos gained immediate access to Native and Popular ERC20 Testnet tokens. This eliminated the need to manually accumulate tokens.

Transaction Speed: BuildBear enables the completion of standard test scripts comprising 10 transactions in under 26 seconds, compared to the 2+ minutes it would take on public testnets like Sepolia. This expedited transaction processing significantly reduces the runtime of contract test scripts, enabling faster iterations.

Explorer: The BuildBear explorer made it easy for Prof. Fábio Santos to view his transactions and debug failed transactions with BuildBear's built-in transaction tracer.

Impersonating an Account: This feature allows Prof. Fábio Santos to pretend to be another wallet that exists and perform transactions from that account.

Forking Mainnets: BuildBear allows Prof. Fábio Santos to fork a range of EVM-compatible chains, such as Ethereum, Polygon, Arbitrum, Optimism, Fantom, Binance, and Avalanche, with a single click. This allows him to effectively test applications on Mainnet without facing any real consequences.