Hi Rajendra,
Sumif is only for Numeric value but this GkRlookup will fetch any data type like alphabet, date etc. also, You can use this function, when you need to view the Break up. For example You have Continuous PO and you want to know how many deliveries are received. Suppose, PO for Rs.500,8000,900,6000. Using the output you will get say $500+8000+6000 now you can easily find that you have not recd Rs900. The same way we can do reconciliations..