I'm pretty new at falling but have been using mostly an open face with a bore cut. The open face is easy to set up for an accurate fall and the bore cut pretty much protects me from barber chairs.
I've been using open face notches since the 70's because that's the way I was taught, and therefor that's all I've ever used. I never cut for lumber or saw logs, just firewood. Over the many years I've seen folks cutting with all kinds of fancy notches that used to lead me think they were so much more experienced then me, and I've cut down hundreds & hundreds of trees. Turns out most of these fools were clueless, that's why I never saw those kind of notches. The people who did those usually wouldn't live long enough to do it twice. I'll stick with my plain old vanilla, tried and true method, it works every time.
Conventional, 'cause that's how I learned, but I hate the butt piece with the taper on one side (or wasting wood by squaring the end). It's only firewood, but I'm a little excessive compulsive. I like the idea of the Humboldt, but the up cut is just too much work. Besides, I like to make my felling cut high enough to let me get that last piece while trimming the stump low.
I do the same thing with the piece above the stump, sometimes I cut 32" inches up for the notch. Then trim the last pieces off down low.
Might do that Bending down low & cutting is getting harder to Then go back & get a round off the stump Wastes a little but easier on the back. I have these rules to follow: ( 12" or less stump)
The trees at the cutting area are not huge Typically 8 - 10 trees to get a cord One load this year was 15 trees, one nice thing in this area is it's thick woods, trees have no/few limbs till you get to the crown, less liming Previous area had older, bigger trees, I got a couple loads there with 6 trees some were 18" (wow ) but much of it was rotten centers some from this years cutting