Aadhaar-based instant PAN allotment service is to allot PAN in near-real time. You are required to quote a valid Aadhaar number and is not linked with any PAN. The e-KYC data of that Aadhaar number is exchanged with the Unique Identification Authority of India(UIDAI). After due process of e KYC data in Income-tax database , you get a PAN.
This PAN is valid. It is not different from the PAN issued by Income-tax department via other modes of application(through NSDL or UTIITSL). However, this PAN is paperless, online and free of cost.