PS also, I've seen some suppliers where the horns are straight and some cranked. What's the difference per se?
I assume you mean the upright of the horn. Most of then have a clearance near the base (where it connects to the cross-bar) to permit the horn to move without having to put a long groove in the wing for clearance.
Some of them have an angle in the upright itself, to try to correct some of the geometry problems that lead to inconsistent rates of travel between "up" and "down". Generally it is an attempt to make the angle formed by the pushrod-ball link-crossbar 90 degrees at neutral, particularly the pushrod from the bellcrank to the flap horn. It's actually a complex 3-d geometry problem to get it perfect, but you can get pretty close with much simpler corrections.
This is extremely important to having consistent and predictable control response.
Brett