Reply to Traktor: Past versions.....

Was just wondering those of you that use Traktor, how many of the past versions/updates do you keep on your laptop? i was looking at what i have since i updated this week to 2.6.1 and i've still got like the S4 software that came with the S4, then everything from 2.0.3 upwards to present. Is it worth keeping them all? cant say i've ever had any problems each time i've updated it.