I just did a Pau Ferro 1pc. neck. Seems to be holding up fine with just Olde English Lemon Oil furniture polish (which is just mineral oil with a lemon fragrance added)
Hmmm. I have a Warmoth neck with Pao Ferro that has only had lemon oil used on it. I's about 4 years old. Never really gave it much thought. Seems to be OK so far.