CRK Warrenty IS Legendary, so you need not worry. I am sure Chris will have some of each in case of a warrenty issue, or they may make one, but they will make it right........As for the hollow grind, I find it to be excellent. I have never had an issue with any of my one-piece knives and I have alot of them.....
The Shadow IV's are readily available, while a tanto is very difficult to find. My favorite one-piece of all time is the shadow I and jereboam I, but they are of the 9" variety and not practical for everyday use unless you are Grizzley Adams. For everyday use and your able to use or carry a fixed blade knife, by far the Shadow IV is the best choice. Thats if you like the spear point like I do. If your a clip point fan, go for a MKVI, its the same knife, only with a clip point instead of a spear point. I just find the spear point to be the mot durable, plus its different. You see clip points everywhere.