Isn't it sort of hard to set the correct pressure if the gauge is pulsating? Then you just are averaging the distance the needle travels and cutting it in half and calling it good. We have several liquid filled gauges on equipment at work. I'd only use a non liquid filled one if it were the last one I had. The only failure I've seen with these gauges are from vibration from the equipment cracking the bordon tube. And these aren't cheap gauges. The pressure settings are pretty critical to the equipment's operation, and I can't see a non liquid filled gauge being ideal. Just my .02.