You will be liable for import tax into the EU, if you get caught and for Carry on they will be seen as all Cary on will be X-ray also if you and partner are all carrying 4 watches a piece then if I was customs I would be suspicious, the reps I would send with any furniture you may be shipping, the most expensive of the gens I would wear, the next most expensive would be carry on and the rest in checked luggage, if you get stopped on the way in by customs and find all the gens then as I say you may well be liable for import duty to the EU