How to chose softserial library use on Arduino project?
I think your problem is that you need 4 serial ports.

With software serial that's just not going to happen:


SoftwareSerial can only receive on one serial port at any given time.
AltSoftSerial is limited to specific pins, and only one instance because there is only one set of pins
NeoSWSerial is kind of between the two. More efficient than SoftwareSerial, but still (as far as I can tell) limited to one instance (it uses a timer interrupt to drive the communication, so can use any pins)


If you need communication between lots of devices over serial then you will either need devices with more hardware serial ports (Arduino Mega, for example), or implement a multi-drop bus system (like RS-485) which only needs one serial port to communicate with many devices. Extra external hardware is required though.