I had relationship with body armour to the point that I had responsibility to check some fellow slackers if they are carrying all plates :)Body armour was issued to all of us, unfortunately, it was more or less torturing device than protection.
I can only talk about local Lithuanian made tactical vest as I've served there. I'm not clear about stats, for us it weighted a ton.
I can roughly say it weights more than 20 kg if fully loaded with neck biceps and between legs protection.
Level IV protection. But fuel kit was only for gunners as they are very exposed.
It was hard to shoot with AK-4, mostly because we had tactical rigs as well, but you can get used to it.
My experience is very subjective as I've only have met only limited kit.
I've seen some old Danish body armours, but never seen them to be issued. Looked like crape, no mole, no nothing.
By the way, is it true that in wet conditions Kevlar plates loose their stopping power? Or is it ceramics? Or it's just soldier myth?