I use medela or lansinoh.. both equally thin. I like lansinoh better, they seem to be more absorbent and when full of milk they don't get as "squishy" like the medelas do so i feel like they will still hold in more wetness. Lansinoh's are also a little bigger which i like. Medelas have a pleat to shape the breast and lansinoh doesn't, but i don't see that as a downfall.
I prefer Lansinoh's brand overall.