This has been discussed here before, here are a couple of examples:

Cayman 2.7 versus 3.4 (Comparison/Differences)

There are several examples in this post by Gator Bite: Cayman 2.7 versus 3.4 (Comparison/Differences)

You can check here as well: Cayman Base / S Differences

You can also check our FAQ that lays out some of the differences: The Cayman Club - FAQ: Miscellaneous

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