I have installed and tuned for plenty of these solenoids and there is nothing wrong with them. Some people dont have the time or desire to cut and splice wires for a diy. This is a great solution for those people.
Medamullet, If you have a problem with their solenoid, why wouldnt you just send it back to them. Btw, if you solder a wire it looses its flexibility as the solder gets absorbed into it. If too much solder is aborbed into the wire, the wire can break that way.