Quoted from MK6PIN:
The glass magazine actually works great in my case...While heavy, I can lift it straight off, as I don't have room to slide glass all the way out in traditional form.
Once you get used to it...pretty convenient, and no constant worry of smudging the glass.
Think art on the cab would be amazing, but glowing side panels are quite unique and killer if game is displayed properly.
As most here likely know, Bally utilized integrated glass canopies in the late sixties and seventies. The most popular game featuring a canopy/magazine style glass is probably 1972 Fireball.
I have always preferred this style for a variety of reasons, including the ability to remove the glass in tight spaces. On the EM games with the glass canopy, you can easily prop up the glass to service the playfield or the mechanicals in the main cabinet. It's a very nice convenience.
In circumstances where the entire canopy must be removed, it simply lifts off. When it is set aside, the glass is less susceptible to damage by virtue of the metal enclosure. How many times have you removed a naked sheet of glass and eyeballed a dozen unsafe spots to set it down, before settling on what seems like an acceptable spot?
The only negative factor, in my view, is swapping the glass itself in the event of damage. I swapped a Bally EM canopy glass (which was scratched, original glass from 1968) earlier today and it can be time-consuming. Nevertheless, glass damage on new games is a relatively infrequent event.
The other negative factor with a widebody canopy could be its weight. Having never lifted an Alien canopy, I am uncertain whether it's especially heavy and whether the latch mechanism is user-friendly.
Ultimately, I would like to see more manufacturers consider canopy/magazine designs for the reasons above.