TT it is
for Sudan You have to do a bit of research in locomotives, but I wouldn't bother too much.
try TT scale at Ebay Germany, might be cheaper
yeah, runnin trains

don't know about others, mine are actually working, but there is no point in activating a train loaded with miniatures - they would topple over in 28mm, the engine is too powerful.
Also, not much use for 2,50 m, and I don't thing anyone wants to wargame with an oval on the table

for a large display setup, why not