I have Reason 10.4 and i am satisfied.
Maybe if someday comes a new plugin/tool for mastering (because i use VSTs for mastering my tracks) i will 100% upgrade without thinking
I use only Reason (main and only DAW) and the VSTs that i use, are working great with reason 10.4.
With this upgrade also you can make music easier (with improved methods) but because of my habit, i prefer to use my old methods for making music. So i will wait to see what comes next