I've only come to this location, so I'm just basing my review on this specific one. This is also the only Perfect Scoop I've been to.
The service here was great and all the employees are really friendly and helpful. They'll gladly give you any sample you want. I particularly liked pink guava, black sesame, and thai tea. I ended up getting a pink guava milkshake.
I wish this place wasn't in the middle of nowhere, or at least closer to my place. It's a nice place to study or just relax with friends and nobody minds if you stay there for hours.
Beware of Durian.