We have compared the two on the basis of speed, security, operations, functionality, support for large files and resuming transfers.
There is no clear winner in this case, but both fulfill the file transfer requirements. If we compare SCP and STFP on the basis of file management capabilities, SFTP beats SCP. Similarly, if we compare the two based on the fast programmatic transfer option, SCP wins over SFTP.
We recommend going through the above listed pros, cons, and key differences to make a final decision.