I spent a good amount time looking all the frameworks mentioned. They all offer good UI components, but Quasar offers more than UI. They extend Vue in many areas that are welcomed.
The design is elegant and clean and there several experienced developers on the forum and chat.
The docs are great for “Experienced” developers, but the “current” docs are not very friendly. However, the upcoming V1.x should have a better Docs experience.
If you just want a simple and good UI, Vuetify will do, but for more serious and pro apps, go with Quasar.