I've done a couple of habanero stouts. What I did which worked well was infuse habanero meat (no seeds) in vodka for a couple of week, then add that at bottling bucket.
I used 1 habanero for 5 gallon of stout, and in my opinion it was too much. It was good, however the habanero take away from the beer. I also noticed the more the beer ages, the stronger the burn is. Kinda expected the opposite!
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