They are indeed Toyo, not Koyo and having fitted one, I would agree that they are fine for general use. I cannot comment on how much stick they'll take off road. But the issue with them is that the grease nipple is in a stupid place which make then usually impossible to grease on the truck.
OK so 2 x 14mm spanner later, you can drop the prop and wiggle it as well as grease it. But, IIRC Steve or some one came up with a very high quality replacement from someone else like Roughtrax.
Chris