I personally have rack systems and visions. I've been successful in both. Many people have been successful with neodosha cages, which I would consider...yellow-lol! I have never used all white cages like Barrs or Habitat Systems, but I guess it would be neat to hear if people have noticed a difference either way in their breeding efforts who do use them. I know NERD uses Freedom Breeder racksystems which have white tubs, and they're pretty successful(understatement of the year!). Here's some of my opinion on Visions. Urates on the plastic of visions can be a total nightmare(get out a scraper!!!), it is possible for the animals to slide the glass over enough to escape if you don't use some sort of lock. This is easier with the smaller cages(lighter glass), but it is possible with the larger cages as well. You can use the lock type they sell or place wooden dows in the tracks to prevent them from being pushed open by the snakes. The top and bottom front is recessed. Sometimes snakes like to hang out there, and that can be an annoyance. The bottom one though I hate as it seems snakes love to defecate under it making cleaning a little more time consuming. They are stackable, but good luck getting them to stack up perfectly without varying gaps here and there. If you use the built in light shroud without modification, and you have a stack of cages, have fun unstacking them to change a light bulb say in the bottom cage of the stack!!! The height of 18" is also a little high and this will limit how many cages you can put in one stack. Four cages is a standard stack where you could put 6 boaphiles(the 11.5" high ones), moonstruck exotics and AP Plastics to name a few. If you do have a snake get out, they love to hide in the recess located in the top middle of the cages. So, there's one more opportunity to unstack cages to locate an animal. Overall, I prefer the look of visions when stacked wall to wall, but I think some cages may have better benefits. Oh, one consideration of the height though that I do like....squeezing into a 12" high cage can be a pain, getting into the 18" high visions is pretty easy. Can't wait to hear what people have to say about breeding and cage color, hope I answered some of your vision questions. Take care!
Paul