My first electric guitar was a Penco SG. Great guitar, I wish I never sold it.
Resale value?... it's hit or miss, depending on the condition of the guitar and if it has the original case. Penco was actually better known for making high-quality
acoustic guitars that are on par with the Martin and Gibson acoustics from the 1970's era.
Oh, and as for the article link, it wasn't 100% accurate. Univox was the parent company of Unicord out of Westbury, New York. Some of the Univox guitars and
all of the Westbury brand guitars that were distributed by Univox were made at the famous Matsumoku factory.
I recently sold my 1979 Westbury Standard (GREAT guitar!) and I presently have a 1973 Aria SG that was made at Matsumoku. I doubled my money on the Westbury, but it was near mint and I had every piece that originally came with it, including the original matching hardshell case, original hang tags, original warranty card and custom-labeled allen wrench that went with it. It was a true time-capsule guitar and a great player, but I couldn't justify keeping it because I like to play 'em, not collect 'em.
I also presently have a 1983 Ibanez Roadstar Series II bass that was made at Hoshino, which was the same factory that made the Penco guitars. That bass is also a great player and a true "battle tank" as far as overall construction goes.
Yeah, I'm pretty much "into" these old Japanese made guitars.
Sooooo.... how about some pics of your Penco? Is the Penco label on the headstock done in Mother-of-Pearl? Those are the best looking ones!