I had tested builds of the mobile version earlier, but used the recovery tool to go back as they were to buggy. Despite all the troubles I read here, after installing Windows 10 on all my devices (the previews had been running on my tablet, two laptops have been updated last week) I wanted the same experience on my phone to. So I decided not to wait the few days till build 10240+ comes out but to update now to build 10166. And I must say, it works like a charme. Haven't experienced any of the bugs mentioned here, it is a smooth ride on my 735.