Other than the additional expense, (and I don't imagine it's an unexpensive thing...) I can't see a downside to adding a 5-pin. If I could do just one thing differently with my Custom, it would have been to have a 5-pin jack installed at original construction. It'd probably be a big ol' pain in the butt to do now, but relatively easy during the build. If for whatever reason I had to send that pbass back the Mothership for work, I'd ask for it to be fitted with one if at all possible.