Bbb has 40 pins of i/o . This why bbb can drive the p10's. Video output is higher quality on the raspberry pi. Bbb has faster processor but do u need it? Raspberry pi model B can drive over 500,000 channels.
So my master fpp is a rpi, 2 slaves with video projectors are also rpi's. 3rd fpp slave is bbb driving a 2x4 p10 matrix.