I've used both the Oasis and the Staun. I liked the Stauns a LOT better. They keep their setting longer, don't require as frequent of cleaning, and are easier to "pre-start" if your existing pressure is close to your target pressure. Smittybuilt has a knock off of the Stauns, they look the same, but I can't vouch if they work the same.
I keep two of mine at 20 psi and two at 15 psi (they are labeled with a piece of duct tape and a sharpie). If I have to go lower, I just adjust them a few turns as they are starting to deflate. I've used them enough that I'm pretty comfortable with where they will end up based on the number of extra turns. Then I always adjust it back the same number of turns when I'm done so that I know they are back to 20 or 15. The 5psi spread is also enough that I can put all 4 on, then when they stop, I put the 15s where the 20s were and there is enough pressure differential that they don't need pre-started.
They aren't the fastest, but they are fast enough. They allow me to take off my swaybar links, or prep something else, or chat while they hiss away. I've never had to sit and wait for the deflators to finish their job, they always end up waiting for me to finish doing whatever else I have going on.