(Insulation Displacement Connections) Pictures to be added.
I have been using the IDC connectors since Vero first introduced them in the late 70's my Nascom 1 had plenty of IC skt IDC connections. I've been using them and re-using them for years with just a starndard vice for making and a scalpel for opening them to re-use them. For the IC SKT type I still have my 1970s collection of soft wood blocks with the collet type IC skts pressed into the soft wood block so IC DILL Pin IDC's can be made in a vice. The vero rep was quite disapointed as back then the press and the idividual aluminum IDC press dies were very expensive.
The only crucial part of using IDC is alining the wires correctly before clamping the vice shut. With care an IDC can be re-used at least 5 times for my reprap builds I've only used old PC serial cables by removing the IDC connector and using the colourd ribbon IDC cable. The IDC press maintains align ment as it holds the ribon cable flat and at 90o to the connector body.
The my old Vero resistor colour coded ribbon cable has an almost flat side and the rounded side the rounded side should be used for the cutting side of IDC pins to locate their V shape cutting blades into. Not sure if the more recent ribbon cable has the same properties.
The screw terminals are only tricky if the wire is inserted under the connection clamp plate. I prefer to tin the wires going into these terminals to ensure a good conection.
Car type Crimp connectors
I personaly do not like the car type crimp terminals as I have seen many fail.
Because of this I always solder any crimp terminals... this kind of defeats the quick connection idea of crimp terminals.
Chocloate block terminals
My preferd method of connecting the stepper motor wires to the addition wire required to connect them to stepper controllers.