This is tough to beat. Not only do you get a 100mm GLASS (not plastic) 10-stop ND filter, but you also get the filter METAL mount and multiple METAL lens adapters. Even if you need to buy step-up/down adapters because the ones included do not fit your lenses, this is still a bargain. Even though this comes in at well below the price of other 100mm 10-stop filters (without the mounting system), it performs excellently.

My unit doesn't produce any noticeable color cast, but I also shoot solely in RAW, so a color cast wouldn't be an issue anyway. The case for the filter is firm, so I don't worry about it very much when it's in my camera back, and the soft lining keeps the filter safe from scratches (so long as nothing coarse gets inside, of course). Better still, the filter mount features a second slot should you wish to use additional 100mm filters (e.g. graduated filters). I point out the size because this is the "standard" in these filters, rather than the more common 80-something mm ones you see in comparably-priced square ND filter bundles that use smaller, cheaper plastic filters instead.

The only issue I found, and this is really just nitpicking at this point, is that the filter mount never really feels very securely attached to the lens. The filter and mount won't fall off if the camera is moved or tilted forward, but the mechanism that attaches the mount to the lens adapter could be a bit tighter fitting in my opinion. Nevertheless, great product at a great price. Anything "better" will be considerably more expensive, and even then, how much "better" will it be?