Question

JJ still makes both of them.

Answer 1

Benefits to purchasing the gold plated, lower noise tubes would probably be miniscule at most.  The advantages though could definitely be a good way to get a cleaner sound (Total Harmonic Distortion would be lower) and the gold plated tips can lessen the potential for corrosion to occur on the tube contacts.

All in all, I would say that purchasing these tubes as a replacement would probably not be a bad idea and could benefit prolonged life of your ADL unit.