fpfrdn - AS has also mentioned the banding in the shadows that you can get with low quality settings in one of his posts (might have been in Matcreators thread...can't remember). Where the really obvious banding in the 0 quality is (right next to the tower on the left)... that wall is one flat polygon.

The artifacts you mean (jagged edges where you'd expect straight edges) - thats purely from having a really low (rpp) render quailty setting in bryce (nothing to worry about lol). Its not the hdri.

Ricky - thats modelled in LightWave. Its a modeller that seems to mesh well with my brain. 

Bryster -  yeah, sometimes, especially when I'm not sure what the final model will be rendered in, I leave the textures off until I know where its going. Also I do a lot my scene setups (organisation) without textures  - just for speed reasons.

Dreams are just nightmares on prozac...
Digital WasteLanD