I don't think it's a safety issue....

I think it's a gun lifespan issue. When pump induced rust killed my Ultra it just leaked (didn't blow up....).

Tank air should not be saturated (holding as much water as possible) since it's delivered at lower pressure than the tank (the water stays there like in a shop comprssor if it exists.....which it doesn't in 'breathing quality air'), unlike a pump which by definition delivers saturated air (unless you strip almost all the water out first) with each pump. The water delivered with the first pumps makes it wet inside, each pump stroke makes it more so as I understand such stuff.

The makers know this, and make reasonalbe efforts to 'rust proof' the inside. Such stuff is evidently not foolproof (the better fool being constantly in development and all....).

You get to choose, but I don't think pumps are unsafe, just potentially dangerous (WRT rust and gun life). Expensive, not hazardous.

Doug Owen