Hacking keyboards & joysticks- most all that I have seen examples of have been soldered
I just completed a control panel using the Ipac and joysticks & buttons from ultimarc(Happ's are the same) and didn't need to solder a thing. The IPac is all screw terminals, and the buttons and sticks all take the same size quick connects that are just crimped on the end of wire(or spade terminals for the correct words)
Drilling, covering it in contact paper, attaching the controls, wiring and conencting to the PC all took just about 1 hour
I havent really looked at the "ready-made" joysticks other than at the pretty pictures to help with layouts and stuff, but I've heard good things about them