Let me start with why, on occasion, i smoke tri tip like a brisket instead of just smoking a brisket. I know tri tip is not easily found in most parts, but here in Southern California you can pick it up at just about any grocery store. Brisket is more difficult to find (but getting easier)...
www.smokingmeatforums.com
Here's the thread that started the "tri tip like a brisket" experience here at SMF. Doing it the first time felt so unnatural, but wow, the results.
That said, NO WAY would I do a tri tip like a brisket if it was more expensive than brisket. That's just silly. Do brisket!