I have used them as room mics, under cymbals, on kick drum, for speech, guitars violins, woodwind instruments and piano, they have perform flawlessly everytime.
They are so small they can be positioned almost anywhere and a set of positioning clips and holders are included in the box. I need to say at this point that when I received my set one of the clips and another tightening tool where missing, but I send an email to Thomann and got sent replacements straight away.
These microphones sound very clear with a fast transient and detailed sound with crisp highs, but also very natural due to the omni polar pattern. It's also worth saying the frequency response has a high boost, but i find that useful most of the times and it can be easily corrected with eq when not needed.
The most flexible mic's i've come across; from working with instruments to pure sound design experiments, these are unparalleled. Highly recommended for a variety of uses, highly portable...you won't regret it.