Back to the original question. Still using SONAR?
Yes and No.
Here's the No.
I took the opportunity to "explore" when Gibson shut down SONAR development. I already owned Reaper and Mixbus. Reaper does not meet my workflow requirement even though intellectually/technically it's the most robust DAW if you take forever and a DAW to customize it to your needs. Mixbus 32C is *not* a tracking or editing DAW (to me), it's a mixing environment that I enjoy when I use it that way.
I picked up Samplitude 3 Suite and Mixcraft 8. Both cute but not my cuppa. I owned Studio One 3 but since I found out about the Arranger and Chord Track features in Version 4 I thought they were going to be right up my alley. So I upgraded. It is now my main day-to-day DAW.
Here's the Yes.
I collaborate with people still on CbB. Once I have created an baseline arrangement of a song (where I'm the initial composer) I make a tracking shell (empty .cwp) with markers, tempo and time signatures. I export tracks/stems/mix and send them along with the .cwp and a handmade Chord cheat sheet.
Since then I have become DAW curious and have acquired ProTools 2019 perpetual, Digital Performer 10, Cubase 11 and ever since getting a refurbished Macbook Pro I got Logic Pro X and I have upgraded to Reaper 6. I also upgraded to Samplitude 4 and Mixcraft 9 (mainly because they were soooo cheap and they made pretty big changes I was curious to try out). I have installed all the DAWs that are fully cross platform ready on both the PC and and the Mac. I'm prepared for Armageddon.