Of these four films my Alta Tensione favourite probably was :

Eye Witness

This film could perhaps be called The Case of the Blind Witness.
But it's Not a whodunit as we get to see the murderer already at the start of the film.
Eye Witness has a great and even stylish opening scene taking place in a warehouse
or Shopping mall at closing time where we get to see two couples and a killer.

Employee Mara (Loredana Romito) has se x with her boyfriend in the office while the
killer, her boss and Floor Manager Jules (Alessio Orano) is peeping at first but then,
when she's alone again, attacks her, rapes her and kills her.
Alessio Orano The Perp Floor Manager looks like Ray Liotta and could have had
worn a sign saying "I'm the Bad Guy" (seen in the cover sleeve pic above).
Parallell to the rape murder up in the office the Blind Elisa/Elina (Barbara Cupisti)
gets locked in when the Mall closes and when Jules passes her on his way out she
witnesses the killer by sound only - The Case of the Blind Eyewitness

Crime inspector Parker (Stefano Davanzati) investigates and Elisa sleuthes.
Barbara Cupisti is very good as blind Elisa and Alessio Orano is fine as the Bad Guy.
One complaint though: That Jules wasn't one of the main suspects as he was Mara's
boss, was at the crime scene and was looking as guilty as Ray Liotta would've.

The film presented in 1.66:1 ratio in english or italian audio DTS-HD MA mono with
english subtitles were the film, all the films, were shot in english.
Extras:

Audio commentary with Nathaniel Thompson and Troy Howarth
Interview with Lamberto Bava (15 minutes)
Interview with actress Barbara Cupisti (12 minutes)

 

The Prince of Terror

Fun Gory Home Invasion giallo horror with super natural elements that supposedly
was to violent for Italian TV.Vincent AKA The Prince of Horror (Tomas Arana) is
known as a Maestro of directing horror films. At the studio he gets annoyed with
his longtime screenwriter (Paul (David Brandon) and fires him.
Then someone starts to stalk Vincent and strange things start to happen at Vincent's
snazzy villa - who could it be?

David Brandon is very good as usual but beware of atrocious acting (especially
from Joyce Pitti who plays the daughter).
The film presented in 1.66:1 ratio in english or italian audio DTS-HD MA mono with
english subtitles were the film, all the films, were shot in english.
FX by Sergio Stivaletti and Soundtrack by Simon Boswell.
Extras:

Audio commentary with Nathaniel Thompson and Troy Howarth
Interview with director Lamberto Bava on High Tension (17 minutes)
Lamberto Bava: The Prince of Terror (18 minutes)

The Man Who Wouldn't Die

An Enjoyable Crime Story and maybe a Giallo.
Five men breaks into an empty villa or mansion and steals the fine art. They tie
up the two members of the house staff and then kill them, but not before one
of the thieves has raped the woman The Perp and our anti-hero of the film
- Gianetto (Gino Concari). He also manages to steal one of the paintings, the
invaluable one painted by Auguste Renoir.

The Boss of the Art Thieves, Madame (Martine Brochard) orders Gianetto to
be killed and disposed of and the gang dumps the presumably dead perp in
the woods. But, Gianetto is still alive and the hunt for him is on.

The film presented in 1.66:1 ratio in english or italian audio DTS-HD MA mono
with english subtitles were the film, all the films, were shot in english.
Soundtrack by Simon Boswell.
Extras:

The Scerbanenco Touch: Interview with Lamberto Bava (22 minutes)
Stephen King Italian style: Interview with screenwriter Dardano Sacchetti (15 min)

School of Fear - with EXTRA CD Soundtrack by Simon Boswell

OK only Psychological Thriller Giallo with No gore and where beautiful Diana
(Alessandra Acciai) plays a teacher at a pre- or early- teenage school who
sleuthes on her own to solve the mystery of a missing student.

The film presented in 1.66:1 ratio in english or italian audio DTS-HD MA mono
with english subtitles were the film, all the films, were shot in english.
Soundtrack by Simon Boswell included on a CD
Extras:

The Tale of Evil Children: Interview with Lamberto Bava (18 minutes)
Play the Game: Interview with screenwriter Roberto Gandus (9 minutes)
Interview with composer Simon Boswell (32 minutes)