I don't feel corner cages offer much useable space for the bird.
Years ago I had a large Prevue cage and was not happy (to the point of not using it) with it at all. The finish on it was so thin that in some places I could see bare metal. If you look closely at the details you will see a thin piece of metal that connects each vertical bar. That piece is flimsy and makes the bars flimsy plus it's impossible to clean, because of its small space in between. The model I had was a Victorian top and I held it together with cable ties because I felt the top pieces were to loose fitting on their own to be safe.
I feel if you purchase the Prevue, you will be looking to purchase again within a year or two.
Kings Cages, while more costly, offers of very thick hard powder coat and would be a good investment.
I only use cages for my Macaws for sleep but a FAVORITE of mine is the AVIAN ADVENTURES HACIENDA. I have one that my GW sleeps comfortably in. You don't need tools to put it together, it has a decent quality coating of Powder Coat and is well designed.
The Double Macaw cages, whether it's the 80x40 or the 32x64 are very nice. I have an older HQ Double Macaw, 32x64, which was made very well. I did experience a new smaller (30x40) model HQ two years ago and I found the quality and thickness of the HQ Powder Coating to be lacking as compared to my older one though.
The large walk in Aviaries are fantastic! I had 2 of the large 5x7 foot ones and they were NICE IN EVERY WAY!