Mine seem to like the darkest ones. LOL, sometimes i'll find two geckos on top of each other in a little tiny half coconut that's in a giant 30 gallon breeder with 4 other hides.
my gecko loves her moist hide. its a 6" bowl, flipped upsidedown with the lid on it, and cut a hole in the top to let her in. i glued fake leaves all over it and then glued the leaves over the hole like flaps. she loves it, i hardly ever see her in her other hides, and her other ones are a rock hide i bought at the store, and another one i made with fake leaves, but its made differently than her moist hide.