No, it should not make a difference. I only mentioned it because this system is "bent" a bit. Unless/until there is a need to get the Syetem Support people involved, i suspect we will use SORT instead of TOOL.And I don't think using EXEC PGM=SYNCSORT or EXEC PGM=SYNCTOOL will make any difference because SYNCTOOL internally invokes SYNCSORT.
150 million is a fair number of records and i'd suggest running a timing test of the way the works correctly versus the incorrect answers that do not have the proper HIT=NEXTs. Yes, doing it so that it works may take some more cpu time, but probably not enough to be alarming. . . And you will have the needed results.