I just purchased a Sony NW-A55 mp3 player to replace my Sony NW-A45 mp3 player due to it going bad. Like the NW-A45, I intend to store my music on a Micro SD card. The songs will be a mixture of FLAC, MP3, and M4a formats with some playlists added. When I purchased the NW-A45, I also purchased the older 256 GB Sandisk Micro SD Card (Amazon.com: SanDisk 256GB Ultra microSDXC UHS-I Memory Card with Adapter - 100MB/s, C10, U1, Full HD, A1, Micro SD Card - SDSQUAR-256G-GN6MA : Everything Else ). I understand that there is a newer version of this Sandisk Micro SD Card with the same storage capacity (Amazon.com: SanDisk 256GB Ultra MicroSDXC UHS-I Memory Card with Adapter - 120MB/s, C10, U1, Full HD, A1, Micro SD Card - SDSQUA4-256G-GN6MA : Everything Else ). My questions are, would I notice a difference in performance between these two micro SD cards such as a faster loading time with the newer Micro SD card when inserted into the NW-A55 player? Is it worth the upgrade to the newer micro SD card or is the older micro SD card good enough for the job and I should save my money?