The only reason to grow Prunus 'serrula' is for its trunk. Its really glossy and I'm told rather phallic when the tree is about three years old. In my experience, this tree grows quite quickly, but will not become any taller than twenty feet. i think it looks better if some lower branches are removed - usually the case when the trunk is the attractive feature. There's another one in the background, together with two specimen River Birchs.
And sorry about the layout of this post. Just cannot get things right tonight.