Well if you are using good texture maps you don't want to use texture filtering as it will blur your maps (it is designed I believe to compensate for pixelation in low rez maps)also you are missing out on many of the benifits of the firefly renderer by not availiang yourself of Displacement maps (of course that also involves fiddling in the material room, which I love but understand many people don't). and you won't get better shadows than is provided by raytracing (you must turn it on in the lights that you want raytraced shadows on) as well as realistic reflection, refraction and other effects(though for those you also need to be comfortable in the material room) my settings are displacement(set at .5 usually), raytracing, and cast shadows.