The 221 is a great cage. Far from being too small, you'll almost find it too big for some kingsnakes.
Keep in mind that small snakes or young snakes shouldn't be housed in that cage, as the space between the glass doors can be large enough for a snake to squeeze through.
Also, Visions have a lip where your kings will hide very often. If the snake is an aggressive feeder, it can lunge down at your hand from above. They will deficate up there too.
Honestly, I find Visions great for boids or larger, heavier colubrids but kind of overkill in size and robustness for the kings you mention. Not bad by any means, just overkill.
Check out www.precisioncaging.com and www.herpcages.com for stackable alternatives if so desired. These cages are light-weight, attractive, inexpensive and good for colubrids.
Mark
>>I have decided to go with Vision cages for my collection of gray bands, Mexican Blacks and Corns based on price, durability and ease of maintenance. Preferably I would like to get one size for all so that I can stack them evenly. I was looking at the model #221's which are 28"x22"x12". I'm pretty sure that these would be good for the gray bands or corns, but that they might be too small for full grown mexican blacks.
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>>In your opinions, which Visions should I go with. I am space concious, but not at the expense of the confort of the animal. I would prefer one size for all, but it doesn't have to be that way.
>>
>>thanks
>>jeff