the size is just right...
what you want to look at is the fact that the vision cage doesn't come with heat, and has a lot of screen venting in the back. (last time i checked...) not exactly the best way to set them up...
check out www.theboaphile.com for his Boaphile Plastics caging, a much better, and competetively priced cage. they offer the same size, which is the right size as well, and will install heat and locks for you.
on the price, don't forget that the boaphile price includes shipping, which vision doesn't, and you'll have to pay to get heating for the vision outside of the purchase price and shipping, which makes the two pretty equal price wise. i just think the boaphile product is better. check 'em out! (there's also a link to the site from kingsnake's front page.)
bc