Another good plastic cage is those from Precision Caging at
http://www.precisioncaging.com/
I'm not one to buy commercial cages. I have always built my own. This year however I have gotten into a situation where I need a good number of new cages and simply don't have the time to build them all.
On the recommendation of a friend I decided to buy a couple of the precision cages to test out. I have been really pleased with them so far.
I have looked at Barrs cages at shows and they are very similar in construction and design, but I personally prefer the precision cages for my use.
Precision offers more sizes and the clear hinges and door pulls make them a little better looking cage.
Both companies make a 24x12x12 cage (precision's is actually 13.25 high) for the same price, but Precision's includes a built in light fixture. I don't use the ones that small, and that was also a deciding factor for me. I prefer the 20" deep models, and Barrs doesn't list this size.
I'm also not fond of "Herpcages.com" drilled into the back of Barrs cages as a vent. It may just be me, but I think it looks tacky, and my collection isn't a billboard for his advertising.
The only drawback on buying from precision is the lead time. It usually takes 10-14 days to get the cages, because they are apparently not built and on hand for shipping, but rather built when you order them. I can understand a small enterprise not being able to tie up a lot of capital in inventory though, and I try to allow for that when I order.