For a fairly high-end Japanese-made product, I don't think it's that steep, personally. A pair of Felco 2 (Swiss) is usually £40-60. There might be a fair comparison.
I've taken the plunge and have ordered the Japeto Hori Hori. I selected that one over the Nisaku as it appears to have a slightly larger guard fron the handle to the blade. Also Japeto is full tang and Nisaku is semi tang and comes with a decent pouch. Based on your comments and other reviews these seem to be the favourites. My OH is horrified as I am rather accident prone but I have promised to be careful - he had tried to talk me out of it. I have a couple of beds with heavy clay and stony soil and its hard to get between the plants to weed properly with other tools. Can't wait till it arrives!
When it arrives take it out of the sheath and wave it at him. That might shut him up.