Vlad P. , Dec 13, 2009; 04:30 p.m.
Ric, you can try this link
They found that Hoya, as economy option, superior than others, including Kenko, but the margin can be slim. I saw your filter on eBay (where most stuff usually overpriced) for $45, so, I guess, they gave you not so bad price. I recently purchased 52mm Hoya HMC Super at Adorama for $26, buying online is usually cheaper. It works fine and I guess so does Kenko.
All stuff like "to protect your camera sensor against the harmful UV rays"..."its thinner compared to Hoya HMC, therefore no haze, its easier to clean coz its not multi coated" is a pure BS:))) ...they also are telling not all the truth. While cleaning HMC filters is really quite a job, uncoated/monocoated glass blocks more light and may allow more flare/ghosting, than multicoated. The most important thing here is the peace in photographer's mind, I mean, when you shoot it's better to focus on composition rather than thinking every moment about your lens protection. For example, I'm a very meticulous person, so I feel good with UV protector rather than without. If you tried shooting with and without the filter and don't see any image degradation or ghosting that's excellent, so you can attach the filter and forget about it at all:)))
I don't think you should remove the protector filter at any time, including night, except when you need to add something else, like polarizer or so.