I have 3 Pis, each with 4 data feeders (FA+FR24+PF+adsbexchange).
In addition, rrdtools/collectd graphson are also installed on all the 3 Pis (installed by jprochazka’s scripts linked in above post).
Pi #1: Ras Pi B+, cpu usage 80%+, temp 55 C
Pi #2: Ras Pi Model 2, cpu usage 35%, temp 50 C
Pi #3: Orange Pi PC, cpu usage 30%, temp 50C