The main thing to note is that these are all German releases, so DVD menus are in German and some of the "extras" are in German only. The main downside of this is that the English-soundtrack version of Bad Taste has German subtitles that can't be disabled, presumably transferred from an original German film print. These subtitles will be more or less distracting depending on whether you can read German or not, and affect only Bad Taste.
I actually bought this box set because I read on dvdcompare.net that it has Braindead uncut in anamorphic widescreen (1.78:1) and with some interesting extras. However that's not the version that I got in this box set. Instead, it has the Laser Paradise "Red Edition" of Braindead, which is 1.66:1 non-anamorphic with the only extras being some horror trailers.
Details from the box
Bad Taste Special Edition, 92 mins, 1.85:1 anamorphic. Mono English, 5.1 German.
Meet the Feebles Special Edition, 95 mins, 4:3 ("Open Matte"). Mono English and German.
Braindead Dead Alive, 100 mins, Widescreen 1.66:1. Stereo English, 5.1 German.
Extras - there is a great 24min documentary from 1988, "A Good Taste Made Bad Taste", on the Bad Taste disc in English or German. This includes interviews with Peter Jackson, his parents and friends, and shows some of the props and filming techniques, so quite interesting. The only extras on MTF and Braindead are some German-dubbed horror movie trailers.
Overall - the movies are what they are. The DVDs disappoint by having only one noteworthy extra across all three discs and non-anamorphic version of Braindead. I can't compare against other DVD versions of these films, but hopefully the details above will help you decide.