INFI is Stronger ,now remember stronger and tougher are 2 different things for steel. If you had 2 identical knives ,one INFI and one S7 and put them in a vise and attached a torque wrench the S7 knife would start to bend before the INFI one.

Toughness means when it does bend it does not break and can be bent back with no ill effects.

154 is also a VERY strong steel and will have more strength than S7 but when it does bend it is more likely to crack and have bad edge deformation.

You will notice that the Muppy tests had no damage to the edge but also there was no bending test like with the S7.

A8 is usually used on things like the front end loader teeth at this nickel mine in Ontario that is the worlds harshest environment for tools etc. The slag from the mine is super hard and corrosive and even A8 teeth are done in a few hours.

A8 and S7 are not cutlery steels which is why no one else uses them. The amazing thing about Busse is their heat treat. Getting S7 hard enough to hold an edge had never been done before. INFI and A8 have so much very very expensive alloy that it is very expensive and is used in heavy industry where stopping production is even more expensive.

Fallkniven attempted to use INFI but abandoned it when they could not get the heat treat right. Jerry is no backwoods guy with a propane furnace. I beleive he taught at an University before the knifemaking gig. Even 52100 through hardened was to tough to work with for a company like Spyderco who are no slouches.

In many ways the coolest Busse steel is the CPM154. I think you guys would LOVE it if it came from the factory actually sharp because it is just so [censored] hard to put an edge on but should hold one like nothing else.

Like northern I run my INFI knives very very thin because they can handle it.
154 can as well and maybe even better if we can just get one with a thin enough edge.