Samsung 30Q's are not 'new' cells.
15a at a cell temp of 25c / 77f - - Samsung designed & rated the 30Q cell for applications where LOT cells are desirable.
(low operating temperature)
At a higher temp (but still very well within a safe temp range) the cell will provide higher amp capability.
Most cells are rated between 45c / 113f ~ 60c / 140f, so the 30Q at 15a & less CDR is a very cool operating cell.
If I were going to listen to & believe what anyone said about the cells we use other than my own company that tests cells & batteries it would be Mooch.
We continually test cells, by the container loads / pallets of cases.
Actual cell manufacturers do not change cell specifications after their release, ever, without notating the change with an additional letter or number.
(one example: vtc5 / vtc5A)
Sure, the QC of any manufacturer isn't perfect, there are a number of low performing cells that slip through every manufacturer's QC.
Most decent power devices do list an input amp limit in their specs.
There is a chance that every single cell you buy is a counterfeit, bin 2 or 3, that is why where you buys cells is most important.