I may have said this stuff before, but here goes again... The East Power, GP, IB etc etc cells are all pushing the boundaries of capacity for SC sized cells. They are designed to burn bright, but not for long. They are also made by Chinese manufacturers, not Japanese ones so their build quality is not as good as Panasonic, Sanyo etc. Cells from Chinese manufacturers are prone to premature mortality (internal shorts, major variations in capacity etc). I work for a Chinese cell manufacturer so have a little experience in this area). If you want a cell that will do hundreds of cycles then you need to go to the lower capacity Sanyo/Panasonic/Saft etc cells (~3000mAh) which are designed for Power Tools.
The matching process offered by myself, Dr V and many others does a couple of good things (1) it ensures the cells have not died early in their transit box and (2) It ensures the cells are matched when the customer first uses them. Any amount of Zapping/Selecting/magic fairy dust is just bull..
It is vital that you look after your cells, Charging at 6A is not a good thing. 4A is OK but I would not go higher. Use a low -dV threshold and only charge cells that are at room temperature. Equalizing does also help but if you get a cell that decides to go internal short circuit then there is little you can do about it.
I personally think the 4000mAh+ capacity thing is a shame. There some really strong, very reliable Japanese cells on the market which offer superior cost/performance, but we don’t use them because we want the ultimate capacity and voltage profile at the expense of life.
Why don’t Sanyo or Panasonic make a 4000mAh+ cell? My opinion is that they are too worried about one going bang.. shareholders don’t like such things. Also, our 'toy/hobby' market is too small for them to be bothered with really... they are too busy courting Makita/Bosch/Nokia/Dell
Rant over...