Guess I could add my two cents to this as I just went for the Sibelius upgrade after going from Mac 10.8. to 10.14. First of all, I think Avid sucks for not allowing me to upgrade my Sib 7.5 to a current version. In comparison, porting my legacy versions of NI Komplete 10, Melodyne and other apps over to the new computer was super easy and cost me nothing but a little time. Avid also suck for buying Sibelius and outsorcing the staff, and for only marginally improving the product (sometimes even making it worse) with each upgrade.
So naturally, I thought about switching over to Dorico. I dowloaded the demo, and, to make a long story short, I had trouble figuring out the most basic stuff. I've worked with Sibelius for about 15 years so its idiosyncracies are baked into my head. Note input in Dorico stressed me out. I followed along a few tutorials, but as I have a big project coming up for that I need to be working efficiently, I'll pass on Dorico for now. I'll definitely come back the next time I upgrade my work computer.
My secret hope is that MuseScore will be ready for professional use in 5 years or so. A lot of my students use it and I see good things, plus its development is in the hands of a talented composer/designer now. You can check his stuff out on YouTube, his moniker is Tantacrul.