Yes, soft leather boots for splitting - on the down, and also up, if conditions allow.
A stiff boot will offer better stability on steeper side hill traverses. The Vans I gifted had 2 plastic pieces to insert in each tongue, but I actually want something that I can also change lateral stiffness from soft to hard as I need it. The latest Spark XDLR has different tongue stiffness, and I expect that it's laterally stiff - which is OK in some cases, but too restrictive or not fun in others.
I guess softer boots that I can stiffen up with inserts as I like and need both fore / aft and side to side will be more versatile and enjoyable.