Hey Tim, I found this little clip at the InstrumentPro website. They sell Vestax effects.

In the early months of 1978, Vestax began producing guitars. At that time, few of the big Japanese brands known today were able to make quality guitars close to the quality of certain European and North American manufacturers. But with a lot of thought, and experimentation with some new compounds Vestax was able to come up with some very innovative pieces. Some of which easily surpassed the quality of any other like instrument that had previously come out of Japan. Some of these pieces went on to be collector’s items, for there durability and design were second to none. One particular item produced, H.S.Anderson guitars, caused quite an upset at NAMM a few years later and is still today a collector’s item cherished by a few of the worlds leading guitarists and song writers, most notably the artist formerly known as Prince.

Hope this tells you something you didn't already know. Steve