One of the problem that I still facing in this build is if I stay for more than 3 min on Edge, the device will become unresponsive. And got really hot. I'm using Lumia 950.
Also on edge when I type a site URL, it will show me the desktop version instead of mobile version of it. I had to close the app by holding the back button, and open Edge again and type that site URL.
The Camera app still crash. But randomly. Device still restart itself, randomly. A lot of app still facing the crash issues (especially apps for editing photos, I don't know if it's the app or the OS..)
In Camera app, after I take photos, and tap on the preview button, it shows blank picture. I had to slide to the previous photo, and slide back to see the photo. This problem was present before I join the Insiders Program.