No matter how you hit it you're not going to get the chemical compounds produced by smoke. And the predomimant effect of these on the body is a depressant effect, thus much less of the couch lock stupor with vapor. I find that the 'sleepy' effect is there, but not until later on when the high has worn off to an extent. The strain you use also comes into play.

I can easily pull an 'all nighter' with vapor. A few hits every now and then and I can stay up all night. Smoke never gave me that option.