Ipod Nano or Sony Walkman??? Please Help!!?

I am a 30 year old woman wanting a music player to work out with. I want exterior speakers, Fm radio and good sound. I want the ability to buy music from like itunes or use limewire. I don't know which one to get. Ipod is like $140.00 at a local store and the sony is $99.00 off line. I've checked review for both and they are both pretty good. I like that I can buy basically any accessories for the ipod but Sony doesn't really have a lot of options. I would like a case or skin for whatever I get and I don't think Sony has one for the walkman. I really don't care about looking cool I just want the best sounding easiest device with the functions I want. See the links to both below. Any help is appreciated!!

Sony: http://www.bhphotovideo0o0com/bnh/controll…

Ipod Nano: http://www.walmart0o0com/catalog/product.d…