It's a great film. I got into The Beatles when I was in 7th grade in 1982 and had just moved to Japan. I had access to a lot of records for relatively cheap due to the exchange rate and my parents supported my obsession. I also tried to get into Paul McCartney and Wings - I got Venus & Mars (just by the cover I guess), and also Wings Over America, the crazy 3 record set. I didn't like it at the time, there was something lumbering about the performance and I didn't pick up on the cool tunes yet. I think that's why I enjoy the Rockshow concert film - I believe Rockshow is from the same tour that produced the Wings Over America album, but released four years later in 1980.
Rockshow is actually edited together from several separate concerts, sometimes within a single song! I noticed because on one tune Denny Lane is playing a Jazz Bass, and it turns into a P Bass mid-song! I had to back up to make sure I saw what I thought I saw. Paul McCartney's bass sound with the Ric is weird, sounds like really dead flats, I kind of like it, it's mixed pretty loud.
Anyway, you can imagine how excited I got when I saw some Alembic gear on the stage! I wonder what they were using it for? Overdrive the front end of the Fender amp it's sitting on?