I replaced the Hoya UV filter I had on the X100T with a new B+W 49mm XS-Pro filter. The B+W seems to be a lot less reflective than the Hoya – at some angles, you can’t even tell there is a filter over the lens. It’s very nice!
My preferred way to carry the X100T around is to not use a lens cap. However, I am worried about scratches and having to wipe the lens element so I have a filter on it for protection. Plus I worry less about wiping or scratching the filter. The reason I had the Hoya UV on there was that it was a leftover filter from another lens that I had. But I really wanted to get the best filter possible (and I don’t care about UV). On my DSLR lenses, I preferred to use a lens cap, and no filter, but the X100T is different in that I carry it around with me almost all the time and don’t want the hassle of dealing with the lens cap if I want to take a quick snap. So I got the highest-rated protective filter as to reduce as much distortion/flare as possible. Plus, knowing I got the filter I really wanted, and did not compromise, gives me peace of mind and no regrets!