Best MP3 Player for Running?

So I need an outstanding MP3 player for running.

Necessities:

-Flash player so it doesn't skip

-512 MB sounds perfect for a few hours of music

-Compatible with a reliable arm band so it doesn't fall

-Waterproof, unless the arm band will protect it from the weather and sweat

-Runs on some type of user-replaceable battery -- I'm not paying $60 for the dealer to replace the battery for me

-Quick and easy to plug-in and add/change songs


Any help is greatly appreciated, thanks!

I Have A Coby One But It Was 70$ no replacable battery but i dont cair about that but the problem i have with it is the right kind of head phone none of them will stay in for me and it psess me off!!!!
Any Suggestions??
Sorry For Stealing Your Post Kinda But You Will Need To Know This Also. :laugh: