In my case, I'd rather like one that generates class 313s, 507s, 508s, 504s, "D-trains", or GWR twin railcars - in other words, stuff that could look interesting on a TMD themed "puzzle" layout.
Oh, well, I guess I might be dreaming for rather a long time ... .
If it's spawned a Bratchill 150 I'd be interested in how you upgrade the window frames. I did mine with a set of etches from Jim Smith-Wright , but lost one packing up at Ally Pally one year. My Bratchill 150 therefore remains resolutely unfinished.......