I`m considering to buy the above mentioned B105.... and I have some questions. Actually I`m choosing between A816 and this one (sooo similar, are they?

). The main reason is because A816 has a much more better battery life, and probably better sound. The only thing better with B105 is it`s price (50% of the price of A816), and the size... because I`ll be using it a lot while i go running.
To be honest I`m a bit scared of the claimed 12h batt life.... How long does it last in real life? Anyone has this kond of walkman? I`d like to hear some opiniones.... So please wirte...