Seems like hollow grinds get a bad rap. Or at least, they are not among the 'preferred' grinds that you see on a lot of the cool kid favorite grinds and blades. But there are a few great companies who have always used them and still do (like Buck). Busse in their knives even big choppers are currently using some hollow grinds. And I've seen others. From the perspective of long term sharpening maintenance, I know that hollow grinds have their challenges. But from a user perspective, they also have their advantages and I think this is why good makers like the above keep using them. As a personal example, a couple years ago I got the Buck "Marksman" folder, it was a special one-off build with S35vn steel and a "full flat grind" blade. Was really excited about it, only to find upon getting it, the cutting performance was quite poor and I thought it was too thick behind the edge--chalk that up 100% to blade geometry, it wasn't the steel nor the factory edge that were the main issue. Then a while later, I got a second Buck Marksman, same steel, but this one with their standard hollow factory grind. The slicing and cutting performance on that thing from the factory is amazing, I don't know if I've had a full-size folder that performed that well without extra sharpening. The takeaway for me was, I decided it makes more sense to be open minded to hollow grind knives again, even though for freehand sharpening purposes, thinking of long-term blade maintenance, I kind of prefer flat type grinds (whether full flat, sabre, etc) over 'curvy' type grinds.