Which version of Sonar do you have? If you have Professional or Platinum you'll have Addictive Drums 2 ( AD2)
If you haven't already done so, register and then go to the web site and audition the drum kits. I'm sure you'll find the snare you want.
With Sonar Pro you get 1 add pak with Splat you get 2.
I have Session Drummer 2 and 3 Addictive Drums 2 and Strike 2 ( Air ) and use them all. But I use AD2 for the majority of songs.
AD2 has a much more in depth interface and is a step up in sound quality from SD. Just being able to add reverb and EQ compression and on and on. Strike 2 is real good too but I've yet to understand how to change kit pieces and customize, If I find a kit I like I'm fine, but I always like to fine tune my kits. AD 2 is super easy to configure compared to Strike. And Session drummer sound flat and lifeless unless you find better samples and add effects to the audio output.
I do use SD if I want to play one of my own sampled drum parts. I sampled my real drum kit and I sampled my Snare about 30 different ways and using different mikes etc. So it's pretty cool for that. AD2 you are forced to buy there kits. I'm not sure about Strike2 playing my samples and need to spend more time with it.