I've just replaced the external glass on my St George oven (model no 904b) for the second time.
It's a great oven but getting on a bit in years and has had a hard life. When we first moved into our place the outer glass had been replaced with sheet metal (and a hefty amount of silicone).
Unfortunately replacement glass was hideously expensive, but I managed to find a second hand oven with intact glass that I could use. (The second hand oven also had shards of glass inside it's door cavity, so I'm guessing it had also had glass replaced at some stage). I'd also heard of people getting glaziers to cut furnace glass to size for them, but I couldn't find any who would do it.
Replacement was not a quick job as the external glass actually makes up a structural part of the door, and nfortunately the replacement glass only lasted six weeks before shattering again (the oven was on but we were nowhere near it at the time). At this point I bit the bullet and bought new glass professionally installed.
The installer told me he didn't usually see problems with broken glass on this particular oven, and issue may have been a scratch in the old glass, or a weakness resulting from the door clipping the top of the oven's storage draw when opening it. We've adjusted the storage draw now and so far so good.
While there's a two year warranty on my new door glass, the installer also told me it's very difficult to get warranty support as it's impossible to prove breakage was a result of a manufacturing fault an not user error.
If it breaks a third time I think I'll be looking for a new oven, so I will be very interested to hear what experiences people have had with other brands.