To your point, the original TSIO-360's only had one temperature probe for CHT and the POH was quite frankly too aggressive for the engines to handle. I have talked with a lot of guys who own this engine, and with a modern engine monitor and engine management, I think its very reasonable to expect the full 1800 hours TBO. I believe @jlunseth went ~2,300 hours on his 231 before doing the overhaul.
I manage my engine very conservatively, never letting CHT's get above 370 even in the climb and in cruise the CHT's are typically 350 or less running LOP. It has a little over 900 hours on it and still has good compressions. I had the rotocoils replaced during the last annual.