I originally got the plant fairly young as a petricola seedling from a serious grower. But it quickly got kind of huge and the flowers are not a match, so I have tried to fill in the dots and guess the paternity based on who else was probably around at flowering time. I could quite likely be wrong -- it's happened before.
Fortunately having a marlothii here that flowers at the same time has brought some similarities to light.
Aloe petricola flowers are usually bicolor, and you can actually see a bit of that in the original picture in the slight change from orange to yellow around the time they open.
There's some good stuff in the greenhouse behind this plant. That is in the park, where this aloe was grown to landscape size. I actually installed it there as a sort of guardian plant, to keep people from trying to slip in between the sheets of shade cloth and take plants from inside.
I'm guessing it will not get much wider but probably significantly taller.