I mainly use VDJ pro, because of the stacked waveforms, the easy map-to-anything, all the plugins available, the way simple sync works, and the way the music library is handled. And oh, Music Plan/Net search is also nice
I also own and use Serato DJ and Traktor Pro, and I would love to have the jogwheel integration from Serato and the effects and general sound quality from Traktor in VDJ
I may start using Serato DJ more.
I don’t think I will ever use Traktor on a regulary basis (library handling, no stacked waveforms and sync handling being the main reasons why)
Best regards
Klaus