Carafa Special II instead of Roasted Barley?

Oatmeal Stout Recipe:

I have never used Carafa II. Will give less roasty flavor than roasted barley, according to the website. Will I still get a stout flavor?

Basically, I will be using 2 row, and a pound each of chocolate and Carafa II.

Dark enough for a stout or will it be more of a porter? Because it's an oatmeal, I am willing to try a bit lighter grainbill. It's a 10g batch and I'm going to add some coffee to one of the 2 carboys.

It'll be black at ~ 34SRM, but it won't have the burnt bite of a stout. It'll be like a porter in flavor, but will have some nice chocolatey/coffee notes.

Roasted barley is responsible for the difference in taste between porter and stout. Personally, I think it'll be great as is. Roll with it.