Cactus Music
Overall the best reason to keep abreast and fully updated is the support and functionality. You fall behind and your on your own.

 
I went from Windows 7 to Windows 10 (didn't like Windows 8) and Windows 10 is snappier. Another difference is that Windows 10 is multi-client with respect to MIDI. This is a major improvement if you, for example, use a synth editor with MIDI and want it open while SONAR is running. From a UI standpoint, I do like the way W10 integrates W8's ill-fated tiles. 
 

My gripe with upgrading is it takes time away from recording to muck about and then re learn how to do something. I feel like I could never fully grasp Sonar right now. 

 
You actually don't need to...a quick story. I've been using Live for live performance since it was introduced. At one point there was a major update, and having helped write the manual for Live 2, I was able to have it updated for free. I later ran into Gerhard Behles from Ableton at Messe, and he asked how I liked all the new features. I was embarrassed to say that I didn't use 90% of the new features, that what I had been using was really all I needed. I thought that perhaps he'd be a little offended, but he was actually delighted. He said that's as it should be - a program should have enough features that different people can use it in different ways. 
 
SONAR is my DAW because I need to do so many different types of projects that I do end up using just about all its features. But if I never had to do a particular type of project any more in the future, there would probably be some features I'd never use again.
 
I understand "if it ain't broke, don't fix it" which is why I stayed on W7 for as long as I could. But I also understand "if fixing it don't break it, go ahead." I updated to Windows 10 in order to stay current and review/test software in that environment, but ultimately found it didn't break anything (except for the V-Studio drivers - it's a hassle to get working under Windows 10), and the somewhat better performance - as well as multi-client MIDI - was welcome.
 

Woh...  thanks much for the feedback, guys!  and yep, it ain't broke...  but to show where I'm coming from I read at the Cakewalk site:
"The current versions of SONAR 2015, Music Creator 7, Rapture Pro and Z3TA+ 2 are compatible with Windows 10.
Previous versions of these products—such as SONAR X3 and Music Creator 6 Touch—have not been tested with Windows 10 and their performance cannot be guaranteed on this operating system."  so of course I panicked. 
I really would like to just carry on and focus on recording if I can, so I'll mull this over a bit more yet.
 
On another note, would anyone recommend an upgrade from my current Studio X3 to Sonar Professional just for the sake of better functionality ?  I might be able to do it for just $75...    I'm not happy with the console view right now, apparently the new releases are a little more user friendly on that screen?

I upgraded the other four PCs in my household (with very few hassles), and then finally upgraded my music PC from 7 to 10. I did lots of preparation, including creating disk images with two different products and updating a couple of utilities. The upgrade process took 2-3 hours.
 
I found that I didn't need to upgrade my Scarlett drivers or MIDI interface drivers. I keep looking around and trying things out, but so far it looks like everything just works. I haven't noticed any performance changes.
 
I think it's generally a good idea to keep your software up to date.

It's kind of dumb not to upgrade. It's like turning down a free safer car than the one you own.
No your old one isn't broken, but good luck trying to find parts for it.

Windows 10 is really slick. Do a backup and go for it.
 

My goodness...   it's not a split decision, more in favor of the upgrade to windows 10

The Anniversary Update is coming out August 2nd which adds some cool new features as well.

soundtweaker
It's kind of dumb not to upgrade. It's like turning down a free safer car than the one you own.
No your old one isn't broken, but good luck trying to find parts for it.

Excuse me!
If Sonar X3 running on Windows 7, is a TOOL being used to make music, and it is working fine. Then upgrading because it's newer/faster/safer/better/etc. is a decision Chevy needs to make.
Is your DAW stable now? You won't notice any stability improvements/
Is your DAW fast enough for what you do?  You may notice some improvement.
Have you been hacked?  You won't notice you're now "safer".
Does your DAW do what you want/need it to?  You WILL notice all the new "features", you may not put them to use.
 
Now, if you're looking for a little excitement, need some new inspiration, see some cool tools you'd like to use or are just fond of upgrading for the sake of upgrading, then go for it.
Either way your decision is NOT dumb.
 
P.S. Tweaker, your car analogy is ridiculous. Software doesn't wear out or need replacement parts. You can keep a solid machine running for at least 10-15 years.
 

I've done the update to Win 10, and everything seems to be working except for Sonar X3 Studio doesn't recognize the drivers for my Scarlett 2i2.  there are no drivers listed in the edit/preferences/ audio/drivers field.  I've tried to uninstall and reinstall the latest driver, but no joy.  Any ideas?

If you go to Edit>Preferences>Audio>Playback and Recording, have you selected ASIO as your Driver Mode for Sonar?  If not, once you select it and click Apply, Sonar should look to see if there are any ASIO drivers available, and IF your Scarlett 2i2 drivers are installed and the device is plugged in and seen in Windows, Sonar should automatically select it and populate the various fields in preferences for you.
 
If the above is NOT what is occurring, could it be that the Scarlett 2i2 is expecting to be plugged into a USB 2 port, and perhaps you have it in a USB 3 port?  (It may well be fine with either, but certainly at one point in time, many audio interfaces freaked out when plugged into USB 3 ports).
 
Bob Bone