I have been a long time Sonar user and I must admit, the new version of Sonar looks great! I am thinking about upgrading soon. but I have a few things that seem to be stalling this process,
 
The first is the fact that Microsoft has announced the release of Windows 10. Windows 10 will be a free upgrade for one year for those who are using windows 7 or windows 8, 8.1. right now you can download As of January 26 2015, the latest build. 
 
Windows 10 Build available to download  is 9926:

Read more: http://www.itpro.co.uk/operating-systems/23119/windows-10-release-date-specifications-and-pricing-announced#ixzz3Q1oUzwS8 
 
So of course my question would be what kind of support would there be for any system that has this version of windows?
 
My second issue seems to be addictive drums. I have AD1 which I got when I upgraded from x2 to x3. right now I have several projects I am working on and they all use AD1. I am wondering what kind of impact the upgrade will have on my current projects. I am more worried about AD2 affecting the current projects. I am not worried about Sonar 2015 affecting the current projects.
 
My solution is to wait until I finish these projects then do the upgrade to windows 10 and then upgrade to Sonar 2015, but it will be a few months before I am done with the current projects. When will Sonar 2015 be cleared to work with windows 10?
 
I am just looking for input on this. What would be the best approach? What would the good people in this forum do?

Since Windows 10 hasn't come out yet and also the fact that Sonar (current version) fully supports Win 7 & 8, I'd stay with this until Sonar has full support for Win 10.
 
Regarding getting Adictive Drums2, you can use your AD1 in your projects and keep all that's within it as it's seperate from AD2 (seperate engine). Meaning both AD1 & AD2 will coexist peacufully with each other or use them independantly. You can also upgrade AD1 (check with XLN on getting a good deal) and use the newer AD2 with the projects you're working on (just confirm this with XLN).
 
Overall, I think you'll be fine with upgrading to Platinum. 

IMHO, I would be so wary of an early build OS update. I ALWAYS wait and see what's going on with the users that got it right out of the gate. Usually within a couple of months all the bugs have been discovered and dealt with and things calm down. It's worth it to me to wait and continue to work.

Windows 10 will launch late 2015.
I translate that to mean early 2016, or maybe just in time for Xmas if we are lucky.

From my perspective I would wait AT LEAST another 6 months after that to iron out the bugs before I would put it anywhere near a DAW environment... Maybe wait for 10.1

Either way Windows 10 is something I have completely ruled out for at least 15 months.. I would not butt an eyelid one way or the other...

Thank you to everyone for your feedback! This forum is great!