LI-ion battery pack from china?

My Lipo battery pack is starting to wear down and puff a little. So I looked online for some other packs, specifically li-ion because of the higher energy density and longer re-charge life and found some on alibaba and banggood. Anyone test them out? If so, do they work? They seem too good to be true.

links would be helpful

Meepo sells a good sanyo 20700 10s2p pack.