I thought that I had posted in a previous thread what I use, but I didn't find it.
From McMaster.com you can buy a over pressure pop-off valve. I have one with a 20 psi limit, but they come in a wide range of pressures. No setting these things, they come ready to go at the specified pressure. Downside is that you need another one if you want to change pressures. I've not ever needed to, 20 has worked for everything I've ever wanted to tackle (like Defense Mine/Stone Cyn, Swamp Lakes, Upper Doran, etc.).
I have this screwed to a clip-on tire chuck. Clip it on and forget it until the noise starts to sound like "raspberries." While that is working on one tire I use my trigger type inflater, unconnected, to lower another tire's pressure. I usually use the clip-on to get me close and then fine tune all tires with the de/inflater.