So when I invested in the gear necessary for brewing all-grain (5 gal batch sizes), I got an 8 gal conical fermenter from FastFerment (http://www.fastbrewing.com/products/fastferment). And I've been very happy with it thus far. However earlier this year, when I did a chocolate-cherry stout, and the final product lacked the cherry-flavor I had wanted I began to wonder if the conical design was working against me. While I don't remember the qty of cherry puree (it was a) what the recipe had and b) what the home-brew store owner advised), I added it at secondary. Poured it right in. And where do you suppose all of that cherry goodness went: straight to the bottom collection ball. Where there is minimal interaction between it and the wort. The puree is too 'watery' to stay in a grain bag... So then I wondered if the classic 'car boy' would have been better choice in that more surface area of cherry is available to interact with the wort. Of course there are pros and cons to either type of fermentation vessel, but I wanted to throw this topic out there and see what others thought.