If you can get decent price Advance tickets then probably not.  Any others, I reckon it might be close….if you are intending to travel off peak.    For others, the Two Together railcard costs £30 and gives a third off most off peak fares for two adults travelling together. So if an individual ticket costs £45 or more, the discount on one trip for two adults can be worth the cost  (£45x2 =£90, less a third =£60, saving £30).    Of course, this thread is about Southampton travel, not