Not all plastic jacks are cheap, nor can you always use a Switchcraft jack. If the system requires a dual source output, for instance if you have both active magnetic pickups and a piezo bridge pickup with a preamp which you want to amplify seperatly (and not at all uncommon situation), a stereo jack won't work. There is a nine pin jack out there for those situations (I get them from EMG or Fishman, though I'm not sure who actually makes them) which has a couple of normally open switches built in that close when you plug your guitar in, which is what completes the circuit (well, one of the switches completes the circuit, the other one is extra) and turns on the active electronics. The're made of plastic, but they are aceptable quality jacks. Now, if Switchcraft would come out with a jack that would work in this situation, I would never use one of the 9-pin jacks again, because their shape is problematic for most guitar designs, but they are not cheap, nor crap.
You do have to be carful when soldering them, though, cause the plastic can melt. That is frustrating.
So, to say it properly Rocket, you should get a Switchcraft jack IF IT WILL WORK in your guitar.
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