Doesnt matter what "branding" it has now, they arent the same OS and as such you shouldnt associate your experiences with Windows Mobile with Windows Phone. Windows Phone is a rebooted OS that runs buttery smooth and doesnt have any of the issues you had with Windows Mobile.
Dont let you Windows Mobile experience define your Windows Phone experience.
Windows Mobile is NOT Windows Phone
That being said I think Apple and Microsoft's model for updating phones it light years ahead and more stable than Android's "maybe" model.