I've begun work on a Roman camp complete with Principia.
The effort was immediately humbling: I underestimated the scale of a Roman camp (basically a small city) and assumed I'd have the same freedom as I did with my Sheffield manor, which I could fit, fully proportional, on a table.
I've had to settle for a lot of compromises, including assuming most of the camp is hidden off table.
My principia is coming along not bad, but I'm hitting a problem with steck (jagged top pieces).
In this case, I concede that System X would be the better building material. At the minimum, it would give me a smooth top that looked better if I chose not to support a roof.
So, I'm weighing whether to migrate the principia to System X on the installment plan. I bought most of my steck at 50% discount from PM USA, so a full System X upgrade seems a little painful--to consider a single wall composed from six units alone can cost $24 from DS.
I may still redesign the principia. A design concession I made was to exclude the atrium that opens to the front door. Yet, this would look very nice (but not in steck!).
-Tim