I'm currently using a Shanling Q1, which I rather like.... it's a good size, feels hefty, sound is great. But it can only handle 10,000 songs in the firmware before it just stops updating the library.
It's not a matter of storage space, my library fits on a high capacity micro SD.
And before someone mentions it, yes, my files are all meticulously organized and tagged, and I COULD just use the folder directory to access all my files, but that kind of defeats the purpose. I want to be able to shuffle all the songs in a current genre, for instance.
And while I could also probably just make a ton of playlists for every possible type of music I might want to listen to.... I'd rather just see if anyone out there knew of a DAP that is designed for large libraries.