I wanted to figure out the difference between Originative regular springs vs. "limited" springs, and couldn't find the answer anywhere, so I contacted Originative's support. This is their exact reply (minus salutations).
The 62g Limited has a little more elasticity to it.
Given that this is true, I think this would mean that the limited versions feel a little firmer and will last a little longer. Could anybody who has both limited and regular springs weigh in here?