I just purchased a Lumia 640 to replace my broken iPhone 5c, I have longed for a long time to dive back into Windows Phone. I've missed the platform. Anyways, should I wait for the offical W10M build, or should I take the leap and go insider? is W10M stable enough for daily use yet? I know they have the 950(XL) and the 550 out with W10M pre-installed, but it hasn't yet been released for older phones? So would older phones have problems with W10M? Pros/Cons?