Hello,
I am using ERPNext for our textile printing facility. Unfortunately there are many limitations in the Manufacturing module, which we have not yet overcome. The biggest issue for us is this one: Packing Slip before Delivery Note, without which we are not able to integrate into our workflow.
If you read the Manufacturing topic on the forums, you will find that the same queries coming again and again.
I too am looking for a vendor who can customize ERPNext, or help improve the Manufacturing module.