I wore Eve for 15 or more hours yesterday/ overnight. I'll admit I didn't have them positioned perfectly, so I had some painful stretch marks on the underside. Having said that, I measured a 38 under, and 44 over this morning. Since they were pointed from suction, and guidance from the inner-cup rings, it wasn't the same as a natural 38DDD measurement but that's what I measured. Arriving home I measured 38 under, no shock there, and 41 over, still technically a C-cup. The technical part matters because, as I said before, it's not the same shape as natural. Yet.
The fact that I've only had these since Wednesday and I'm already approaching 100 hours in them, without water blisters or red rings and odd shaping, is a testimonial to the quality of the skirts and the quality of the pressure regulation of the pump. It does go through some AA batteries, though. So make sure, again not sponsored, make sure you've stocked up on your Amazon basics. You'll go through a pair every other day with the pace you're able to comfortably maintain.