It is funny that you have just posted this because I have just spent the last hour testing out some newly purchased tracks from Beatport. What I have discovered is very surprising. Basically, every single track purchased has a slightly drifting tempo throughout.
I confirmed this by loading the raw tracks into Rekordbox, and the tried to use the Tempo Grid feature to line up the beats. I had to make several adjustments per track, on average.
Next, I used Ableton Live with the raw track files. I began warping the tracks by aligning the beat transients to the Ableton Live grid. Then I Rendered to AIFF the warped track so that they have a constant tempo, perfectly on grid. Then I loaded the new version of each track into Rekordbox and I found that the Rekordbox tempo grid now lines up absolutely PERFECTLY. No need for any adjustments. Just marked my Cue point memorys and I was done.
When playing the new version of each track on the CDJ-2000 players, the tempo was much more stable. I needed fewer corrections on the platter.
One final note, I attempted to use Master Tempo on the warped version of the tracks and I still had the audible jitter issue. This does confirm, in my opinion, that Master Tempo is still not a useable feature in current state. It does cause the music to sound off-beat.
I am not sure if you are having an issue with your CDJ-2000 player or not.... but I did want to report that I have found that pretty much any purchased music track will have a slightly drifting tempo. For this reason, any time I purchase new music from now on.... I will be loading it into Ableton Live, warping the tracks to a constant tempo, and then Rendering a new audio file. Then I will load the tracks into Rekordbox and use them on the CDJ-2000.