I emailed Perlick asking about the variant logo. They probably won't get back to me. Want to know which is the earlier variant, etched or tooled in logo. I believe the etched is the earlier. Here's my hunch:
1) The promo ad for the Perl faucet (website) shows product with etched logo. It's extremely common for ads to be shot using prototypes or pre-production samples.
2) Believe the etching is a secondary process as opposed to the "engraved" logo which would just be part of the mold tooling. In other words, the etching is likely to cost more and slow manufacture and therefore likely to be changed.
3) The etched "P" is not as visible as the engraved "P". This is the company logo. In my experience, top brass always wants their logos more visible and more traditional. And if they saw an item that didn't live up to their expectations of that, they don't mind changing a design last minute.
If I'm correct and anyone collects breweriana, those etched faucets will be worth a few dollers more in 50 years.