music from usb and playlists like realplayer

So I am using Realplayer for the most part, though I do use Coolplayer and VLC for some things.
My problem is that I like Realplayer for only one reason, because it has that function of recognizing my mp3 player and letting me download music to and from it, and to set up playlists for the mp3 player.

Does anyone have any good apps that are out there that does that? It doesn't have to be fully portable.

I just want something on my usb key that uses the Music folder on my key(orwhereever) and recognizes my Sandisk Clip, and lets me download music to and fro w/ playlists.

I looked at the players that came up in a search for "music playlists mp3" and I don't recall seeing something that would recognize me mp3 player as a site to download to and fro.