The pcm will keep it safe.
the "balance" will look all pretty and nice for a while, then it will continually get off more and more. this does not effect the safety, BECAUSE YOU HAVE PROTECTION, it more effects total capacity and longevity. it is only after time where the balance will keep falling off more and more. and if the pack is to be used when it is not doing so well also, like say when cells are at 80% capability, it will rapidly fail to hold descent capacity.
Example, if one cell item is 5% below the others, cycle , cycle cycle , cycle, that one cell item will effect the balance of the pack way more than that 5%, because the protection will STILL stop the whole charge ,as ANY cell in it reaches full.
and then eventually, it is not even working the charge alogrythm correct, because it is adressing cell items at different voltages. it cant SEE the cells, only the series set.
one solution is to provide at least a Maintance balance capability, even if you don't balance it regularly, that way you can See inside, and rebalance at least a few times.
an Inticement to balance is that All of the cells will be FULLY charged :-) you want that don't you?
most things you gotta worry about with the protection curcuits, and that they will do the actual amps you desired.
you can visit www.bestechpower.com
for more information.