I've been using a HIBY R3PROII and have been enjoying it quite a bit. Battery lasts for ages and the sound that comes out of it is pretty decent. I have considered using an old iPod, but I really felt like I wanted something that supports modern microSD cards as my music collection is several hundred gigabytes in size. It's OS isn't amazing, but it does the job well enough. I really wanted to avoid an Android-based DAP as I am trying to avoid using my phone and that would just contribute to it I feel.