Rick Hinderer Knives Eklipse 3.5" - Hollow Ground Slicer Blade / CPM-S45VN Steel / Black G-10 & Titanium Handle ZC00062464

Great ergonomics. The handle is very comfortable in the hand, and the blade shape is great for a variety of uses. Flipper opens effortlessly and frame lock is rock solid. One of my favorites in my collection.

I have a regular Eklipse with a slicer grind, and I picked this hollow ground version up as well to compare the two; eventually planning to sell whichever one I like the least.
The below are my experiences with just one sample of both the flat ground, and the hollow ground Eklipse.

HRC: Hollow = 59, Regular = 57(Crucible recommends S45VN at 59-61).

Pivot tolerance: there is no detectable pivot or detent lash on the newer hollow grind knife. My 3 year old regular Eklipse has pivot lash, and a sloppier action.

Average thickness behind the edge FOR BOTH KNIVES: 0.02"

While it is a bummer that the hollow grind is hardly noticeable (I really mean this), and that they both have similar thickness behind the edge; the real value is that the distal taper thickness is significantly thinner compared to the regular slicer grind Eklipse. At the tip, the stock on the hollow ground version is about half as thick as the regular. This allows the hollow grind version to cut or slice (instead of crack) an apple into two pieces, unlike the regular version.

If you have an Eklipse already, I would not purchase the Hollow Version. You are not missing out on much of anything. If you are looking at getting your first Eklipse and the hollow ground version is still available, I would opt for the hollow just for the slight boost in cutting performance.