Natural coffees can be funky, as can Sumatras. So one might expect a naturally-processed Sumatra to be particuarly funky. It might be, but the one I have from PT's is remarkably clean.
Source: http://www.roaste.com/CoffeeBlogs/fincawhd/PTs-Natural-Sumatra
Source: http://www.hawaii-aloha.com/blog/2013/02/06/no-snacks-for-hawaii-pigeons/
Source: http://www.toastedfoot.com/2013/01/cigar-review-cremo-classic-maduro-intrepidus/
Source: http://www.paradise-found-in-maui.com/grand-wailea-hotel.html