drain cables direct 3/8ths i/c cable

Ok so im debating on buying a new brasscraft 5/16th cable my usual washing machine trap /really hard elbow kitchen sink ant bath tub drain machine or trying on of the 3/8ths x 50 ft i/c cables off drain cables direct .The logic is the 3/8 I/c one although double the price might last longer but,not sure if it would have enough flexibility to pass through an old rusted galvanized washing machine trap ? Anyone have any experience with either of these cables in similar situations?

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