functional as a Hoya filter should be. Nice new design cuts a few mm off of the lens length compared to my old Hoya UV.

Tiffen filters are always reliable; they're the only ones I use. 

Tiffen 49mm UV Protection Filter

Nice tight fit on my 49mm lens filter. Feels solid to.

Hoya HMC UV was my secondary UV filter. I have a B+W UV filter for my 24-70mm L Lens, but I wanted one for my Tokina 11-16mm wide. I didn't want to spend as much money as I spent for my B+W, so I gambled and took a chance with this one. Honestly, I don't see a difference in quality of my images. Perhaps there might be some if I really look into and compare, but overall, this one performs well.I also chose this one over the other filters because it was the slim frame one. I read that the normal ones might be too thick for a wide angle and you'll notice it in your shots.

Used for lens protection only. This is a good quality filter that you would rightly expect from Hoya. Better ones area available but at a premium price in comparison.

I have used HOYA filters for many years and have never been disappointed. The UV filter protects the lens and does not detract from the quality, sharpness or resolution of the Lens; all at a very reasonable cost.

A good filter to protect the lens, no lose of IQ as exoerienced with another Hoya skylight filter,

I had a Hoya 1B HMC Skylight before, which broke over a pebble and saved my Sigma 30mm f/1.4 (on a Canon 40D house) when I dropped the bag (a Soligor Classic Line, size M) from about 1m / 3.5ft.I decided on this filter mainly for the cost savings compared to a Hoya or Dörr etc, and am very pleased.I'm not a pro photographer, and use this filter mostly indoors (as mentioned above, it sits on the front of a 30mm f/1.4), so UV influx is rarely a problem anyway.That said, I haven't noticed any bad influence at all of this filter on the picture quality I get, and the fit (thread size and cap compatibility) is great and build quality seems all good so I'm a happy sailor.