I use iTunes match myself. 256K ACC sound amazing, These are not your grandmas MP3. I have all my movies on a plex server. And I don't need to take all my photos with my. While I still wish I could justify a 1TB, and I really do. 512GB should be plenty. At least I hope so.
When I travel, I have my DSLR with me. Since I shoot in RAW+JPEG, I fill up cards quickly, and will offload pics to my rMBP. That extra space on the SSD comes in handy for those situations...