Help with combined knitting

[kuwona]

I was just practicing the combined knitting method. I find it a lot easier when doing ribbing. What I want to know is this...if I do the ribbine using the combined knitting method, can I switch to the regular method when I come to the stockinette stitch part or do I have to continue with this through the whole body of the sweater?
Has anyone used this method? What are the pros and