I was curious about this kendo under wear that was on Kendo Jidai and Kendo Nippon magazine. I didn't know Mazkiya USA had them til recently.
I was skeptical about wearing a undergarments, since most of the guys don't wear anything under gi & hakama. It's hard to wear undergarments during humid hot summer but seems like it has the technology of having your skin cool while you sweat.
Since these are sold separate, I bought the top and the bottom.
I'm still experimenting myself with this to see how it goes but for now I could tell that I don't get cramps on my legs since the undergarment helps the blood circulation.
I know it is pricey but it's worth the money.