Hi Guys, [and sorry for noob questions]
 
 
What's the difference between having Session Drummer as a simple instrument track and a folder with All Synth Audio Outputs: Stereo? Could anyone provide a link to a nice tutorial?
 
 
Thank you!

For a simple single instrument like bass or piano, I use a simple instrument track.
 
For drums, I use the All Output options because I want the audio for kick, snare, toms, etc, on separate tracks so I can mix them, adjust EQ, vary reverb by drum, etc.
 
When you choose All Outputs, you will get a lot of outputs.  Then you go into the Session Drummer Mixer tab and choose which drum goes to which track.  For example, if you choose 1 for kick, the kick will go to the FIRST AUDIO OUTPUT (which is not necessarily Track 1 in your project).  2 for snare will send the snare audio to the second of those tracks.  All the MIDI to control the drums will be in a MIDI track that should appear after all the audio tracks.
 
You can delete any tracks you don't need.  Personally, I keep things simple and use 1=kick, 2=snare, 3=hi-hat, 4=toms (in stereo), 5=overhead/cymbals, 6=any other percussion (in stereo).
 
Some people use a lot more tracks and put each tom on a separate track, and that's fine.  I have never felt the need for that.
 
In a simple instrument track, all the drum audio comes out on the same track.  That track will have an audio tab in Inspector and a MIDI tab.  If you open Staff or Piano Roll views, naturally you will see MIDI and not audio.
 
I use several virtual drums, including Session Drummer and EZ Drummer.  If you have any more specific questions about Session Drummer, I'll have to open a project that uses it and look.
 
Best of luck.
 
 

There are two videos which in http://www.cakewalk.com/CakeTV/SONAR-University/Master-Class called "Drum Production I" and "Drum Production II" which illustrate setting up multiple output Session Drummer. It uses an older version of SONAR but the concepts are still current and there are notes at the bottom of the videos about the differences using the Skylight interface.

By using multiple tracks for drum output, you can mix/EQ/etc each drum track in Sonar. As a simple instrument, you have to mix within the VSTi.

As already mentioned, it really comes down to the level of control you need/want.  I use Additive Drums as a Simple Instrument Track when the song simply needs no more detail than that, and it's worked just fine (many of my tunes on the Songs forum use SITs).   If anything, I'll usually insert the synth (AD or others) as a SIT and then add additional audio tracks pointing to the synth if I feel I need additional control over kit pieces (usually Kick and Snare).   As with most things mix/production related, YMMV.  
 

I've done what Steve C does most of the time by using SIT . Lately I've been diving into using the multiple outputs option more because as my song would develop and take shape I would find myself adding another instance or even a different drum VST ...in some cases it was to fatten things up , in some cases it was to replace things...
I guess what I'm trying to say is while my drums are still in a placeholder state I find it much easier to keep things simple by using SIT . Once things are close to being dialed in , then I will open up a new instance of the Drums as a multi output and copy over my edited midi track to the multi drums midi track ...
fwiw , I learned that I have to make sure I add the midi track option to the new multi track  Drum VST . This is to be able to copy over my edited midi and have the multi drums play them on the outputs I have assigned in the drum mixer ...
( not having a midi track for the multi was the root of all my problems in learning how to set up the multi ) anyway it finally sunk in
 
Once happy , I will delete the old SIT edited tracks and old VST because I have them where I want them in the new , plus what ever extra outputs I have that are not being used will also get deleted .
 
Kenny 

Thank you guys, much appreciated!
I also found a tutorial that may be useful for beginners like me as it illustrates a work with drums - and specifically - multi track drums, what's the idea behind, how to do it right way and how to tweak it.
https://www.youtube.com/watch?v=-X-fIfLFtvM