Long story short, I plan to connect two companies over WP2MP links. For this purpose, I plan to use SXT 5 HPnD ac elements. The picture shows the actual situation. Both companies (B and C on the picture) are 530m away from the main unit (A in the figure). The distance between B and C is 200m.
My question is: For the situation at point A, can I use SXT G-5HPacD (25°angle) or do I have to use the SXT G-5HPacD-SA (90° angle)? Both costumers wants/expects around 100/100 Mbps UDP throughput.

Anyone?
Your angle is around 21 degrees.
It could work with the 25 degree version, but you will be using it at the near end where the gain diminishes.
Better try with the 90 degree to be safe.