I'm seeing a full deployment time of about 140 seconds (from the time I push the run button until the application appears on my device). This is with "use fast deployment" enabled. It takes 180 seconds without that option. All the other settings are the default for a Xamarin Forms project using PCLs. I've verified similar times from a plain Android application.
The messages in the VS toolbar say "build started..." for a long time and eventually changes to "packaging application" after about 90 seconds. The status bar often reverts to "ready" (or goes blank) for long periods of time (but while still building). Visual Studio freezes during the build process sometimes. The output window doesn't get populated until the final 10 seconds or so, which makes me wonder if it's doing nothing for the first 130 seconds.
The physical device is a Sony Xperia Z2 running Android 5.0.2.
This has made learning the framework extremely frustrating and borderline unusable.
Perhaps of interest is that in the Xamarin.Forms application, blanking the form dropped build time to 60 seconds after restarting VS. Adding
xmlns:local="clr-namespace:DemoApp;assembly=DemoApp" and the list view that I'm trying to create brings it back up to 140 seconds (and crashes the application because I must be doing something wrong with binding, but the slow build time has made experimentation difficult).