occide
I know about the non-linear mode, but it's not really helpful. It reduces the latency (and midi dropout) issues but doesn't remove them completely. Then I have LP EQ and Comp on like 12 tracks + maybe some buses, means I'd have to toggle like 10-25 instances manually between non-linear and high quality whenever I want to hear "what it would sound like". Sorry, but that's nowhere close to a good workflow.
 

I come to think of a couple of things(excuse if I don't know the plugin as such):
 
#1. Have checked if maybe high quality is automatic when rendering?
VST plugins has such an input, so all rendering may transparent in high quality.
 
But maybe I don't know the difference in those modes, just ignore if I am on thin ice.
 
#2. Did you look at MixRecall - that is supposed to switch these kind of aspects of a full mix in one go?
So doing that once for each mode, changing modes on all, you can rather quickly go back and forth and listen for differences.
 
#3. Control Groupings are substantial in Sonar, ability to apply changes to same control on many instances.
But not sure how it also applies to loaded plugins - just have a look.
 
#4. CAL scripting - might be worth a look if you can make a script that do those kind of flips of a control in a plugin - directly or send midi ctrl to plugin to change mode, NRPN or midi CC controller. all plugins having automation would have some of those abilities.
Often forgotten cool feature in Sonar, sadly enough. There used to be a forum for CAL, but think it is long gone.
 
I have a license for Sonar Artist 2015 - and thought about upgrading to Pro at some point.
Major thing for me in Professional would be routing stuff like patch points and aux tracks, so if you use those check comparison chart what differences are.