Solana's recent post-quantum security tests, conducted in collaboration with Project Eleven, revealed a significant 90% reduction in network speed. The trials, aimed at preparing for future quantum threats, showed that quantum-resistant signatures are up to 40 times larger than current cryptographic methods, severely impacting transaction throughput. This performance hit raises concerns about Solana's scalability and execution under real-world conditions. The tests highlighted structural vulnerabilities, as Solana's design exposes public keys directly, increasing the risk of quantum attacks. Project Eleven CEO Alex Pruden emphasized the urgency of addressing these risks, noting that quantum systems could potentially recover private keys swiftly. While full network upgrades are complex, developers are exploring interim solutions like "Winternitz Vaults" to secure individual wallets without immediate network-wide changes. Despite these efforts, broader adoption of quantum-resistant measures remains a challenge.