PROS-good fit (they stay firmly attached because they are screwed in and not pressed on, which is good as I tend to use my Nano hand-held or on a stick and it does get bumped around a lot)-good knurls, makes it a lot easier to screw them on/off-they are robust (I didn’t try to scratch them, but I’m glad they are resistant, as that is my main problem with attachable filters)-I see no reduction in sharpness (though i tend to edit down to 1080 anyways)-decent value for this set at £39.99CONS-slight image colour shift as you move up the various strengths (not an issue if you set white balance properly)-photo number 3 in this listing shows a fundamental lack of understanding of what ND filters are for (they are for slowing down shutter speed, or allowing for use of wider apertures in bright conditions, neither of which are demonstrated by the images in photo 3)NOTES-it’s always nice that I can set my exposure to a more “cinematic” look, even though few seem to consider that a desirable look when working with action camsMY STAR RATINGS:1* substandard, mostly cons2** barely acceptable, cons outweigh the pros3*** meets the basic requirements, cons balance the pros4**** good product, pros outweigh the cons5***** exceptional, all (or almost all) pros