Tempted to buy a keyboard with at least 61 keyes, after touch, mood wheel and pitch bend.
Looked at this one  M-Audio Axiom Pro
According to M-Audio it will "automatically map to commonly used parameters of popular software instruments and digital audio workstations including Pro Tools, Cubase, Logic and Reason* systems." (HyperControl Technology) Sonar is not included. But it has ASCII keystroke support and I guess that means that midi-controllers to Sonar could be set manually. The sister keyboard Axiom AIR 61 doesn't seem to have this ASCII keystroke support nor HyperControl Technology. I guess there are similar keyboards that do have support for Sonar midi control. Roland A 800PRO?
 

Although Cakewalk is no longer uder the Roland flag, I doubt Roland drastically changed any of their controllers which were previously working well for Sonar X series. Imo the novation controllers map best across a wider range of products right out the box than the competition but my comparison was far from scientific.

I own a few novation things.. and the build quality IMHO is not as good as my original axiom mk1..
 
novation.. I would stick to automap mode with it, due to using a sonar template that pretty much messed it up.
 
the axiom mk1 was not good integration wise with sonar.. but decent build quality
not sure what keyboard I would buy now tbh... maybe a roland or something by yamaha perhaps if they do just controllers.

Thank you guys. Yes I found an interesting article about Novation Impulse used with Sonar X1 here: http://www.harmonycentral.com/t5/Expert-Reviews/Novation-Impulse-Keyboard-Controllers/ba-p/34630896
Seems like strong candidate. M-Audio is tightly connected to Pro Tools and Yamaha, which also owns Steinberg (Cubase). Figure that their keyboards would have compatibilty issues with Sonar then. 

Thing about the Roland A-PRO keyboards is that you have ACT.
I'm guessing now that ACT is dead??

Given a chance to do it again I'd probably go for a Novation keyboard, I'm a Focusrite fanboy after all.

I'd be glad if Novation just work with Sonar out of the box.

the novation sl2 is a huge step up in keybed quality... if that is important to you..

CakeAlexS
Thing about the Roland A-PRO keyboards is that you have ACT.
I'm guessing now that ACT is dead??

Probably so.  Soon to be replaced by GUCE  (Gibson Universal Controller Environment)
They'll say it "Juice" but we'll call it "Goose"     : ) 
 
Brian

 
There's a whole forum dedicated to this question :
 
    Keyboard Controllers & Sound Modules