"But Frusciante now calls the Shadows Collide with People recording experience “frustrating.” Although he doesn't disown the album, he speaks with more affection about the demos he made for it with Klinghoffer on a Tascam 488 mkII 8-track cassette recorder."

In this transcription of an article from the June 1996 issue of Sound on Sound magazine, Smith says of his demo recording process, "When I do [them] at home, I play a lot and build up the song. I use a little Casio home keyboard, a Musicman bass and an electronic Casio guitar with plastic strings, as well as an Ovation 6 string acoustic. Then there's a Tascam 8 track Portastudio."

In this article about Madlib's early bedroom studio, we can clearly see the 8-track Portastudio in the first picture. He also talks about it in his Red Bull Music Academy lecture (http://vimeo.com/29834586), but doesn't mention the actual model.

According to the liner notes of his first, self-titled album, Panda Bear partially recorded "Panda Bear" using a Tascam Portastudio 488. This information is verified by the album's release details on Discogs.

"The Grime And The Glow explores the dark and beautiful relationship between death and humour. Recorded in different spaces, all on a Tascam 488...."

Many articles have cited Chelsea Wolfe using a Tascam for her earlier recordings, but this one I chose because it cited the exact model.

Can be seen in this photo. Looks like it's the MKII version

In this post, Captain is showing a Portastudio 488 MARK ONE

Alasdair Maclean recorded The Clientele's debut album, Suburban Light, on a Tascam 488 multitrack cassette recorder.

before getting a functioning reel to reel he used cassette multitrackers, including this one! https://youtu.be/2OjmL4NjxDg

Visible Instagram posts dated January 14, 2014 and October 17, 2014. According to Frankie and the Witch Fingers bandmate a Dylan Sizemore and Glenn Brigman, it was used to record Sidewalk and the eponymous Frankie and the Witch Fingers.

It’s Psychedelic Baby Magazine, “Frankie And The Witch Fingers interview with Dylan Sizemore, Alex Bulli and Glenn Brigman” by Roman Rathert (September 16, 2014)

Dylan: So far there are only 40 Sidewalk cassettes floating around, but we’re supposed to have a new batch soon. The tape came along in a very organic way. I saw Glenn at a show and he said, “You should come over and record some tracks”. The next day we had the title track “Sidewalk” fully recorded. A couple of weeks later we had the whole tape. They were just supposed to be demos we dumped off of the Tascam 488. It was super fun, and I haven’t stopped hanging and recording with them since.

[…]

Glenn: “Revival” is part of a new record that will be coming out on Permanent Records later this year. I recorded it with help from Josh Menashe in my bedroom onto a Tascam 488 last fall. It features a 12-string electric that’s actually a knock-off Rickenbacker and a Farfisa Compact Duo.

Musician’s Friend, The Hub, “Vibing with Frankie and The Witch Fingers” (November 14, 2017)

Glenn: On the first couple of records we used Tascam 488 cassette machines. We switched to a Tascam 388 quarter-inch machine for the third record, Brain Telephone. We are currently starting to record with a Tascam 38, which is a half-inch tape machine.

"mkII" variant in particular. Has been used on pre-debut releases and demos, as heard on a YouTube interview.