Iridient has the best overall look and feel from the Fuji Files I have seen so far. Since I run a Macbook Pro 15" with bootcamp, I can run Iridient. They have a great feel for both the overall hue of a raw especially the blues and the details in the greens.
Photo Ninja does a good job, and would be my 2nd choice (as I still feel LR leaves a lot to be desired as it quickly gets too plastic looking certain parts of images) and Capture One still has a bit of trouble with the greens. Photo Ninja also can leave a strange over claritized (too much clarity) with the Fuji files much like I used to get with Bibble and my original S2 conversions.
By far the single biggest issue I see with LR conversion is areas where it's dark against light, like a brown oak leaf against a blue sky. The conversion seems to have a lot of trouble here and leaves what I find are strange artifacts.
For sharpening, I find that it's best to do just a bit in the raw conversion then move to Focus Fixer which does an excellent job on the Fuji converted tiff.