Thanks for the responses! Doesn't look the easiest of things to do though. I do think that there is a lot of demand for this sort of thing however.
Scott is quite right in that for something like tiles, a texture would be better for performance, but for things like panels, where the joints and setting-out are critical, you do need a component like this.
Also single linear arrays with the same property. Stuff like copings, kerbs, ridge tiles and that sort of thing.