There were a lot of reviews and information with different brands can be reach in the website but not so much of this Naniwa Gouken Arata, here I do a review base on what I use and stock.

The whetstone came with a almost clear plastic storage case without a base attach and without a nagura. The case can also be use as a stand but it is not tight fit, so it will move forth and back. Secure in an adjustable rubber stand holder in the long run for steadiness is recommended. It is lightweight and height is 15mm compare with 25mm height of Chosera. The length and width stay the same at 210mm (L) x 70mm (W). Each whetstone color is the same as the Chosera and represent their respected grit. The machine printed grit number can also be found by the side.

For the first time before using it, wash the surface under the tap water to give it a good clean. Lightly tap or spray with some water along the way helps the sharpening or polishing process. Wash and clean away the swarf after each session with water. Checked with a pencil and flatten with a diamond plate once it start to dish, edge and corner to avoid cuts and clean the paste under running tap water to prepare for the next sharpening session. Allow air dry in room temperature before storing away. No rapid drying with hair dryer, heater or fan.

#400 Coarse - Removal of chips, change of profile and repair work is easily accomplish with this #400. The speed is as good as the Chosera. Because it is fast to remove metal, it is recommended to frequent check the outcome to avoid over grind for first time users. This is the whetstone for those who need to fix the above mention issues. If a lot of heavy removal work need to be done, I would suggest to pick the Chosera since it will last longer given that it is 10mm thicker. 

#1000 Medium - The hand feel is smooth as the Chosera and the speed is good. Scratches from the #400 coarse grit can be easily removed. Comparable to higher than #1000 of others brands. This is a great #1000 for all medium sharpening that is not aggressive. Quick touch up or sharpen a blunt blade is easy. If planning to get only one whetstone for general maintenance this is a good choice.  

#3000 Finishing - It is exactly the same as their elder brother in every aspect. Smooth fine feeling and fast polishing. The edge is very sharp and start to throw a semi mirror finish effect. If no further refine polishing is needed, this is a great finishing whetstone. Also a great stepping whetstone towards higher grit polishing of #5000 and #10000. 

#5000 Super finishing - It takes only a few passes to achieve a very sharp edge and mirror effect after progress from the #3000. Very smooth and fine hand feel. It can be the last mirror polishing whetstone if no further progression need to be make. The hardness of this whetstone is perfect for this job.

#10000 Super polishing - To achieve the sharpest edge and highest mirror effect, this is the ultimate grit in this series. It is also the more harder and fast whetstone in this series. No surprise to see only black swaft cover on the surface. May seem a bit difficult for first time users to work on but after a few tries this whetstone can be rewarding and familiar to be use with ease. 

For beginner to start with, owning a #1000 at first will be an all rounder. Two sets included of #400+#1000 for most common use of restoring and general sharpening. Two sets of #1000+#3000 for general sharpening and fine finishing. Three sets included of #400, #1000 and #3000 will cover restoring, sharpening and fine finishing. Three sets included of #1000, #3000 and #5000 for general sharpening and higher level of finishing without restoring work.

The newer series Gouken Arata have no loading at all in each and every grit as with the Chosera. The speed in the #400 Chosera is a tad faster, the Arata is a little gentler but still fast. Both series of #1000, #3000 and #5000 is very similar. It is suitable for many profession as well as amateur or home users. Although it is only 15mm height it will still last quite a long time. However, active users may seem better benefit with Chosera because of it thickness with value. I use Chosera and I really like this Gouken Arata very much. They both have the very similar great performance but the Gouken Arata offer a much better value. I will highly recommend to try their high quality products.

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