These small diaphragm condenser mics are great for studio use. I've never heard of them being used live and they're pretty delicate so I wouldn't recommend it. They are condensers so they need the power supply to operate. They also are very tiny, and can be broken easily so extreme care is necessary. They are expensive to fix so don't break them unless you want to spend lots of dough.

OVERALL OPINION

I've been using these mics for about 8 months. I love the high, crisp sound you can get with them. I primarily use them as overhead mics. I tend to use them as my go-to for drum overheads, because they pick up the full sound of cymbals incredibly well. For this reason I also enjoy using them on hi-hats. I have used them in tandem with AKG C12's on a piano to good effect as well.
I have assisted on a session where the engineer used them on an amplified Fender Rhodes piano. That sound was amazing. I would definitely try to do that again if a player wanted it to be amped as opposed to DI. I tried using them as room mics but wasn't as impressed with them in that capacity. Overall though, I've been really happy with them.
That being said, these are pretty expensive mics. I've seen them go upwards of $1,200 for a pair. Make sure you can get a pair of used ones in good quality unless you have a lot of cash to throw around (lucky you!). I don't own this mic but I plan on getting a pair of them as soon as I can afford it, in the meantime I'll continue to use them at the studio. I would certainly recommend them to anyone who records drums and/or cymbals.