I am the one who use UV filter.. but i only use B+W and Hoya HD.. there are a few reason i use UV filter:
1) Those top quality filter has coating which is 10 times easier to clean than the glass of lens, even L lens.
2) I am using Crumpler 7 million on my shooting and traveling, it need to put 4 lens and 1 body and 1 flash: 24-70 2.8L, 17-40 f4L, 85mm f1.2II, 50mmf1.4 5dm2, 600ex-rt .. there is no more space for me to put those hoods, so most of the time i do not use hood..
3) with UV filter, i can switch my lens faster as i don use lens cap anymore, as those high quality filter does not scratch easily: all lens just squeeze into my bag without cap if i having photoshoot with model..
the disadvantage of UV filter : u lost just a little of sharpness and contrast even though it is B+W or Hoya HD.. only noticeable if u compare both image at 100% scale.
