Firstly, EVERY spider has some degree of 'wobble' which flare up at points in its life, and go away to nearly nothing.
Spider 'wobble' is the word used to describe a spider's inability to keep its head completely steady; often they have a very mild shakiness to them.
Spiders also have a tendency to have issues with equilibrium and often do not keep their heads completely level, or in worse cases their head will "spin" while they try to figure out which way is up/down. Another ailment that comes with the spider genetics is called "stargazing" which describes the snake staring up at the ceiling of the enclosure with its head extended outward. The wobble is directly linked to the gene; this means there is no way to breed out the gene to have literally zero wobble. The severity of the wobble is not genetic, and completely variable. A spider with a severe wobble can produce offspring that have minimal wobble, and spiders with minimal wobble can produce offspring with severe wobble. Trying to line breed 'minimal wobble' spiders is a waste of time since the severity of the wobble is random. I will say that I have only seen one or two spiders that I will say had a severe wobble, and that didn't stop them from living out an otherwise normal life.

NONE of the above issues are of serious concern, or are lethal in any way. There has only been 1 spider that was recorded as being so bad that it could not function normally (as was already mentioned by another member). I have had the pleasure of working with/had first hand experience handling many spiders and spider combos and I can tell you not one of them was so bad that it raised concern. ALL of them did show the typical symptoms (which if you have worked with enough balls, any person can pick up a snake with spider in it and find the wobble) but none were severe.

Spiders do have some pros that people should talk about,
Along with the nerve issues causing wobble, spiders also seem to be more "mechanical" and instinct driven than other ball pythons. They tend to be calmer, and much more focused on the simple things like feeding and breeding. Spider ball pythons are AMAZING feeders on average. Once they start eating, they eat well, and continue to eat well. Most breeders will confirm that working with spiders and spider morphs makes life easier. Spiders also tend to be quick to breed, and consistant breeders. Males are known to breed young, and know what they are doing almost immediately, whereas some ball python males are reluctant to breed the first few tries. Lastly, Lastly, spiders seem to be less concerned with being handled and often seem to have no discrepancy with being moved about by hand. It is almost as though their brain is also thinking "Food, Breed, Food, Breed, Food, Breed" and unless there is a meal infront of them, or a snake to lock with, they are just relaxed.


Hope that helps!