I've noticed that some CZs have thicker silver triggers, and some have thinner silver triggers. Seems like this varies even when it's the same model.

Any explanation?

Thinner vs thicker trigger...

The trigger in the top pic is a newer style trigger that I believe you'll find in most DA/SA models. The trigger in the bottom pic is the older style. Most people including myself prefer the older style. I personally find the newer style very uncomfortable, and I've had a couple pros tell me they felt the same way. I wish CZ would do away with that new version.

I pretty much only shoot single action CZs now, so I guess it's not a huge deal to me anyway though.

When did CZ change the design? The newer trigger, is it uncomfortable because of the sharp edge or something?