Gas content and coal thickness are good, Perm is not good for...

Gas content and coal thickness are good, Perm is not good for these shallow coals...

But to give an impression to the original question by @Gharp, here some best cases as reference
(I know, such figures depending on reservoir properties, well completion, production method, etc. but just to give an impression...):

A well in the Hancheng coalfield at 430m flows at 180 mcfd,
a well in Raniganj at 430m flows at 280 mcfd,
a well in San Juan Basin flows at 450m flows at 530 mcfd.