Whenever I’m shown something I really don’t like and I’m obliged to comment , I say I find it “interesting”.
“Interesting” is a convenient word. You are invited to someone’s house (not a close friend obviously). The decoration is unbearably tacky. The person feels the need to show you around the place. After you’ve seen the wood carved Louis XV furniture, the china cabinet and the endless plastic and porcelain knick-knacks spread out over every available surface, you are asked the dreaded question: “So what do you think, you like it?” You cannot say it’s a nightmare, so you just say: “It’s very interesting…” and nod to stress it.
A woman shows up in a party wearing a dress that doesn’t do her any favors. She asks: “I bought this dress today, isn’t it lovely?”
“It’s very interesting [nod, nod]. Mm…I really need to buy new boots (always good to subtly change the focus of the conversation)”.
An acquaintance buys you a crappy present for your birthday. It’s always acquaintances; your friends know what you like. They should anyway.
First, hide your shocked/displeased look on your face. Then: “It’s very interesting…thank you! [nod, nod, nod and smile]” Mission accomplished, no one’s hurt.