They are both made by BPI.

The winchester has higher quality standards.

The sling "The Claw" was offered only on Winchesters when they first came out. CVA now uses them, along with the winchesters Solid stock. Thats why you'll notice on some of the higher end cva's they weigh close to 9lbs without a scope. The new cva's also now have an improved pad on the rear of the rifle that some claim to be almost exact to the $40 limbsaver.
The cva buttpad costs $14.

Winchesters also were the only BPI at the time,that you could buy with an Stainless Steel barrel. CVA now offers this on their high end muzzys.