I imagine that rewiring Reason to Sonar could be the best of both worlds.  But the reason I have stayed clear of Reason, is their past refusal to support VST plugins.
 
Reason, now with your favorite VSTs included, would appear to include a lot of additional creative tools that could be useful to begin a song arrangement with.  Then just record the song's tracks into Sonar for polish and mixing there.
 
Personally I would be happy to just see the features offered by Reason included in Sonar ... one DAW to rule them all!!! 

sleeper

Stevethesearcher2015
The mixer in Sonar is better but the Redrum in Reason is just excellent at programming drums.

 
I think that SSL based mixer in Reason is a great! A beast! 
 

I'm guessing Steve is referring to the layout and workflow of the mixer, and not necessarily the "sound".
 
Reason's console is modeled on the SSL 9000, so from that perspective is fairly unique, as other DAW consoles (with the exception of Mixbus) are designed to be neutral-sounding.

I like Reason 9's new vocal pitch edit feature.  The upgrade to 9 saved me from having to start upgrading from Melodyne Essentials.  I haven't tried rewiring it into Sonar Plat yet but am going to use Reason 9 just for vocals.  So VST support isn't something I care about...ATM.

It looks worthwhile for a first proper DAW which at least will let you get the bare bones without exporting out to another sequencer.
 

From the Manual...
 
VST compatibility in Reason

• Reason 9.5 and later supports the VST 2.4 plugin format.
• VST 3 plugins are not supported.
• Both Windows and Mac VSTs are supported.
• Since Reason is a 64-bit application, only 64-bit VSTs are supported.
• Multitimbrality in VSTs is currently not supported - only one sound per VST can be played back at a time. If you are using a multitimbral VST it will only receive on MIDI Channel 1.

Multitimbrality and VST 3 not supported? hm... seems I wont be ditching my DAW anytime soon.

It will probably be just fine for current Reason users who want to add some VST synths to their projects.  The target user probably isn't a heavy user of multitimbral sampler libraries.

sleeper
 

• Multitimbrality in VSTs is currently not supported - only one sound per VST can be played back at a time. If you are using a multitimbral VST it will only receive on MIDI Channel 1.

 

 That was never supported with Reason's samplers. BTW some of your plugins may ask for reauthorization.  

It is my understanding that in rewire mode VST support within reason is not available either.........  Bummer

How do I get Sonar Artist to rewire Reason 9.5?
(Currently it works with Reason 8 but I cant see how to change it)
 
Thanks