The Silverfox "C" actually looks well enough. The B101 they do is probably the only one likely to be available for some considerable time, though SSM might still have a few. I don't know what it is about the proportions or curves, but I've yet to see a TRULY convincing B101 model..... maybe IRM will put this to rights some day.
If a Hunslet can sell out - a loco there were only ever three of, which didn't last all that long and which were almost completely confined to one route - there will hopefully be no argument against making a B101 model, even though they were very much "southern" engines - the only time you'd see them on the Midland was the weedspray, and I'm unaware of any heading up the GNR, certainly north of Drogheda anyway.
For now, I'm awaiting the IRM announcement re a "C", and reserving thoughts on a B101 until or unless IRM make an announcement on one at some future stage.