I'm also interested in Smooth Jazz. I suggest you open the Style Selection dialog and audition all of the Smooth Jazz styles--there are around 65 of them in my version (2011 Everything/Audiophile). Click the "Load Song Demo" button for each style which will give you a nice tune that was designed specifically to show off the style you've chosen. I did this a while back and it was time-consuming but well worth it. What I found was that the MIDI styles (non-RealTrack) were more diverse and "interesting" sonically because of the use of various synthesizer sounds, but they sounded a little computer-y because they're MIDI and I don't have the highest quality on-board synth sounds. The RealTrack styles sounded more like real people playing (naturally), but are more limited sonically--e.g., you get lots of phased or chorused Fender Rhodes in the rhythm section ala 70's/80's Joe Sample. (There might be more diversity in the 2012 jazz/R&B RealTracks which I don't have).

As for straight-ahead jazz: like others, there are so many I can't name one at the moment. I tend to choose ones that reference piano players who are a little more harmonically sophisticated, like Herbie Hancock or Wynton Kelly. I will tell you who my favorite straight-ahead drummer is, though: Terry Clarke. Just about all the styles I use tend to include him. You can choose a filter in the Style Picker that will only show you styles with a particular drummer.

Good luck!