The Serpa looks nice. Is the retention easy to release?
If you have good trigger finger discipline already, then it is very simple to release. Just press the length of your trigger finger against the side of the holster and that'll be enough to release the retention. It doesn't need to be a whole lot because if somebody tries to grab your gun they are going to wrap their entire hand around the grip and not be anywhere near the retention button.
Slow is easy, but it takes practice to do it
quickly every single time because you have to make sure the button is getting pressed an instant before you start pulling on the gun. The harder you pull on the gun before the button is pressed, the more difficult it is for the button to be pressed enough to release the gun. (If that makes any sense.)
Also, if you are used to drawing from an IWB holster, or an OWB that fully covers the slide, you will be plesantly surprised at how little upward movement it takes to clear the Blackhawk SERPA holster and get the gun pointing at your target. As you can see in the earlier photos, it is cut so it doesn't cover the entire slide.
There is now a less expensive version (Sportster) that only comes with the paddle. The paddle still locks in very tight if somebody were to try a gun grab, and paddle holsters are a good choice for people who might be out running errands and end up somewhere that doesn't allow guns. You can just take the whole rig off without undoing your belt and lock it up in the car.
Oh, and Midwayusa.com usually has them in stock.