Personal use or not you will still have to pay import duty and VAT if its value is above the threshold (which I can't remember - in the region of €150 though) for bringing things into the EU. I took a 22" LCD as hand luggage SLC-MSP-AMS with NWA a couple of years ago. I was nervous as I was seriously stretching the allowance, particularly with a large laptop rucksack as my 'personal item', but NWA didn't complain at all, and it went into the overheads (A320 and 330) with no issues. At Schiphol, however, the Samsung box was spotted immediately and I was taken to one side. Fortunately I wasn't importing anything else and had a receipt to prove the monitor was just under the threshold, but all of my baggage was searched for anything else they could charge me for.