Nice, but not necessary - Ghost Inc Standard 3.5 Pound Trigger Connector All Fits Glocks Drop In 2105-B-0

You can only read and watch so much about glock triggers before you just have to put your finger on one to see what it's all about. Having bought a G19 gen 4, I gave this a go.

The pull is lighter by my own judgement, but I don't think the difference is significant. If you have good fundamentals, this will not be the difference between hitting and missing.

I'd say it's a nice to have but not necessary by any means.

Cons:
I do notice that doing a press check is a little more difficult. Something about the initial motion of the slide has more of a "catch" to it compared to the stock connector. The force required to move the slide is not consistent with this connector compared to stock. Peeping in the back of the gun, you can see the slide engage the connector. The shape must stick out a little more than stock, because this is where the extra resistance is coming from.