If it "looks" used, you should normally not have any concerns. The problem is, the customs chaps at BOM are quite fickle. Last November, I brought in a few extra bottles of booze above the permitted limit of 2 litres, and they said nothing. In December, the guy checking my bags insisted that I prove to him that I had brought only one bottle of perfume (as I claimed) and not several (as he claimed to have "seen" on the x-ray machine). YMMV.