Yes! I did last april. the accomodation itself is fab- I stayed in the extrovert loft, all glass and steel and concrete: very modern, minimalist and uber sexy stylish. Its very clean and well equipped. Location, is a LITTLE out of the way, but i walk with elbow crutches so that is a main issue for me. But having said that the tube station is 5 mins walk, and on foot, the nearest area of cool bars and restaurants in only abou 20mins away. The studio itself was really great but because of the walking i would think twice before going there again.
I don't know the Miniloft but the location isn't bad. With S-Bahn you reach almost every point of interest within a few minutes. There are also some restaurants and bars in walking distance. The area itself isn't very nice but safe and central.
We always choose self catering accomodation and very often the kitchenettes are equipped with the bare minimum. Our "Classic Miniloft" had a kitchen with everything you need and the decor is probably to most people's liking. I liked the very civilized trusting attitude: key under the door, no deposit, replacing drinks in the fridge. Location was good but one major hiccup: as it is very close to a hospital we had ambulance sirens ALL NIGHT LONG, I was pulling my hair out after day 2. If you have problems walking up stairs check whether the studio is located in the old building.