A renowned testing institution recently carried out a practical assessment of the storage capabilities of the 1TB variant of the iPhone 18 Pro Max. This particular model employs QLC flash memory, and during extended periods of high-intensity write tasks, its flash memory speed experiences a marked decline, even dipping below the performance levels of certain basic microSD cards. When compared to the iPhone 18 Pro, which boasts 512GB of TLC flash memory, both models exhibit comparable performance in weighted 4K read operations. However, a noticeable disparity emerges when subjected to mixed read-write workloads. The 1TB iteration of the iPhone 18 Pro Max relies on high-speed SLC caching to manage sudden bursts of write activity. Once this cache is depleted, it sequentially resorts to simulating a TLC buffer zone before ultimately writing directly to the QLC flash memory, leading to a precipitous drop in speed. Moreover, as the storage space becomes increasingly occupied, the deterioration in performance becomes even more pronounced. While these differences may be imperceptible to users during everyday use, those utilizing the high-capacity version will undoubtedly observe a significant reduction in speed during extended high-write scenarios, such as recording 4K or ProRes videos.