Sound advantage? seriously?
To me all the software sound the same and scratching is where Serato beats Traktor any day of the week.
I do not see any software of the big 3 as an “advancement” over the other, they cater to different style DJs.
VDJ has tons more features than Traktor and Serato has a way easier workflow.
If you are happy with the DJ software you are using, then there is no need to change anything.
The only advance you can think about is switching from Serato Intro to Serato DJ, as it will give you loads more options and be on par feature wise with Traktor (sans remix decks, which I have yet to see anyone use effectively other than Moldover).