I'm curious what the actual performance differences on Platinum (Cakewalk's Last vers.) are between Win7 to Win10?

The giant elephant in the room with regard to older operating systems is that when MS says a new version of VC++ will not install on a particular version of Windows as they did with XP in the SONAR X2a days (if I remember correctly) then it will be over for that OS and Cakewalk because one thing developers do is grab the latest libraries as soon and they are available such as in the days of touch coming to SONAR. MS said the VC++ redistributeables that supported touch just won't load on XP. - I was there when it happened on a development machine. To be clear XP will run SONAR up to X2. X2a and beyond you need 7 or better. Not becsause of the Cakewalk code so much as MS refusal in the Redistributable installer to install on XP. It's mean, but that's MS and they like to control their ecosystem.
 
If they did it once they will do it again. And MS would just love to kill windows 7.
There will come a day if it already hasn't happened, that you'll need a particular update level on 10 to load the latest what have you.
 
This fact alone chased me to 10 even with all the update hassles.
 
When Cakewalk closed and I knew I wasn't forced at that point to be running 10, I almost went back to good old 7. But now that Cakewalk has been resurrected, I'll think I'll stay on 10. :-)
 

In ref to differences for audio.  On a Roland Octa-Capture (USB2 Connection) the latency was lowered by 1 ms.  That may not be a lot to some but I thought it was enough to be noted. 
 

I noticed something similar to Fireberd's experience when I moved from Win 7 to Win 10 a few years ago on my core2 quad. Now I'm on 1803 and it's working well (on my current machine) but MS has added all sorts of bloat to Win10 that wasn't there when I first did the upgrade. So I think it's tough to make the comparison -
I initially felt great about Windows 10 and it's been fine in my own case - but I always feel that it's one update away from pandemonium.

Noel did say there were some changes made to Cakelabs coding to make it run better with W10. I believe him. 

I haven't seen any data to show a difference, but I have a hard time believing that anything runs faster in W10 vs W7. But of course if some optimization for W10 has happened, I guess it's possible. It would need to be mind blowing for me to upgrade. Maybe W10 is better when using a touchscreen.

Thanks guys.  Now, for my follow-up question.  If I have a Win10 laptop, am I able to run that same license on my desktop?  If so, then how do I install that creature?  Whether I am or not, should I delete that C:\ partition and reformat?  Finally, is there any particular flavor of Win10 to install as there was on previous OS ver.

If the Laptop is setup to log in with a Microsoft account (e.g. Hotmail) then you have "digital entitlement" and can install Win 10 on the desktop and you log in with the same Microsoft account.   I'm doing that with my desktop and laptop. I have a Hotmail e-mail account and that qualifies for any other Microsoft site or use.  
 
But, you can use a Product Key from the laptop on another PC.  

Win 10 has a better audio stack (the WASAPI option in Cakewalk) and I think, but am not sure, the MIDI port limit has been either eliminated or increased. I actually like Windows 10.

I'm on XP and staying there.  LoL
 
If you find an OS version you really like, and have all the DAW tools you need, then just make backups of everything to be sure you can always rebuild a machine if needed.  I just did this recently - 100% brand new parts except for the motherboard.  Had very little issues except for one wrapper component that wouldn't run in multi-processor mode correctly and caused me a lot of headache to track down.  But that aside it was LOT easier than rebuilding a whole new DAW using the latest OS version and having to repurchase a bunch of new software, etc.  And worst of all, having to re-learn it all.  Not to mention spend a ton of time stomping out bugs and glitches, always wondering if you'll ever really be able to get everything working smoothly.   Uh...no thanks, not for me!  I don't know how you guys do it frankly.  If I kept updating operating systems and plugs and host software and drivers and hardware there's no way I'd ever get any real work done, and I'd be spending a fortune in the process.  LoL
 
You guys can poke fun at me all you want, I'm staying on XP with my trusty RME interface.  
 
Sonic