Let's talk about some stuff about the mines:
The mines WILL block your point of view IF placed directly onto the face - you'll be seeing the little mine attached onto your face, bleeping in red. If you attach it in front of the body, let's say - on the foot, you'll still be able to see it in first person view - most likely if attached to the anus, it'll still be visible (haven't tested that location yet), but the back of the head is the perfect location, unless you're willing to get attention of others about someone walking towards a guy with a mine on his head - works really well, just like a plasma grenade - I like it!
For damage distance, now I can't remember quite well, but for sure it'll hurt you from 13 people distance (or 13 floor tiles on as_resident_evil, in the main white corridor), but the part that I can't remember is if it'll damage you to "hurt" status, or take you 50 HP.
If you are on a 3-4 people distance from it with an overshield (200hp, acquireable on ttt_lockout) with a body shield, you WILL still die and get thrown far away.
Also, my favourite part - it penetrates walls - you can plant it on the other side of the wall, and blow the camper inside of it! It's really my favourite ability!
You can't carry more than one at a time, but you can plant as many as you want in the same time - if you're willing to actually waste credits to be throwing mines on the ground JUST to switch each other, so you can plant them all, BUT you can't detonate them all in the same time - each mine gets blowned by it's detonator - so when you use one, just pick up that other detonator!
It's pretty balanced, unless you're willing to increase it's fallout reduction on damage - that won't affect the balance negatively - honestly, this is basically for me a C4 + Jihad + Plasma Grenade in one, since it can act like a Jihad, I can call a T buddy to plant my mine onto my head and rush into a room, and it's main purpose - I can attach it to someone & they'll just go douche around & walk into a huge group of people - Plasma Nade's useful feature <3
Tl;Dr:
Mines are OK - I like them
Good distance - 13 people (next to each other) distance & you still get hurt
Wall penetration - ignores map obstacles
Good Damage - Will demolish a powerful enemy even from close-to-medium distance
Easily visible - the prop's easily seeable, if it's dark - it has a red bleep, and if you're blind - it beeps also!
Traitor-friendly - gives instruction about using it, AND it works like a radar - if you walk into it's range after you've been warned that it'll be blown, then it's your fault - you would easily see who has one planted from which T-buddy.
Fun & trollish - time to walk into a huge group of people with it attached!
Green = Advantage
Yellow = might be unbalanced; Questionable; Medium
Red = Disadvantage