I had hastily left feedback when we first tried out the players, before I knew they were hacked and before my sister's player died. I left them positive feedback, in which I complained that it didn't really play mp4s. I put a follow-up comment on my feedback. Here are the feedback and the comment :

Happy with products. Don't play mp4's, as promised, but lots of other features!Seller:
yf-tech (
45350
)
Dec-31-09 18:48
- Follow-up by way*** (Jan-16-10 07:01):
FRAUDULENT!!! 2GB HACKED MEMORY CHIPS. NOT 8GB, AS SHOWN.
-- (#120495712413)
I think it's too late to ask for 75% refund, since I agreed to 50%. They have yet to answer me on the amount due back to me, though, so this battle may not be over yet. I'll keep you posted!
Herm
__________________
Chipod specs :
serial # 4512482ADF0FE
revision 2.00
chip vendor Actions
chip part # ATJ209X/ACU75XX/ATJ2063
firmware version 9.5.54
AK2025_BOCO
hacked 8gb player, really 2gb