Can you even see you pit that is mounted to your trailer? Are there any rules that say it must be enclosed or anything. If you can't see it then it doesn't matter much what the public thinks so long as it's good food. Personally I'd go with insulated cabinet smokers. My bubba kegs you see are insulated and the hours I can get with just a few pounds of lump is awesome.
In regards to investors, I'd be really cautious going that route. What are their expectations?