Living in Bavaria my local model engineering exhibition is "Faszination Modellbau" held in Friedrichshafen (end October/ beginning if November) down at Bodensee (Lake Constance). The exhibition is held over 3 days in about 8 large halls. Apart from the stench of IC racing cars in a confined space and the sulphurous smell of coal fired miniature steam engines running on trackes spread over 2-3 halls and traction engines chugging around, I have nothing to complain about.
My partner would have told me if something was wrong or didn´t smell right She humours me by coming along. She seemed quite happy to look at the model railways whilst I looked around at the various stalls and exhibits.
This place is big with high ceilings and large display halls (almost aircraft hanger size). ( Perhaps that is the deciding factor).
Just in case you think this was a purely German event there was a group of Welsh steam enthusiasts running their engines there last year and in the trade display with a Myford lathe. All the usual scale model firms were also there together with all sorts of specialist firms.
Slow fliers, all sorts of vehicle models and aircraft models were on display. A bit of anarchy.
Apart from that a good cafeteria and a beer garden. In the middle of all this we sat in the beer garden whilst the Zeppelin based there took off low over the the exhibition area on a tourist jolly and proud model owners circled the area on riding on miniature traction engines (picture if you will a guy in bavarian dress with a ZZ top style beard riding a miniature traction engine).
One problem for me, no clocks.
No BO problems but we arrived fairly late , just as the early birds were departing clutching their RC helicopters etc.