What are unique features of erpnext which other erp’s dont have???
This is open ended question and i think no one would have the answer for it as there are so many ERPs in the market. However you could still read more about ERPNext features on erpnext.org and compare them with your own experience.
It would help community answer this question, if you test ERPNext for your requirement and compare it with past experience of other ERPs.