i think this law applies to all charge distributions just like ohms law applies to all voltage and current distributions. The limitation may be that it is difficult to evaluate for some charge distributions and shapes.
It is not limited by charge or shape distribution....tht is not mathematical limitation for any law....only complex solution we can call it.......
But i feel limitation should be...
1) medium of application should be homogeneous..
2)2 charges/charge body must be far apart such tht each are independent of each other havin no effect on others....