The top level answer is that although the 1050 was a great piece in its day, that day has somewhat passed. If you are satisfied with the sound and performance of the 1050, no need to upgrade.

On the other hand, the 1070 not only adds all the latest surround modes and 7.1 capability, it has modern conveniences such as lip sync delay and many more system/speaker configuration options than the 1050..,including the on-screen menu system not avaialble in the 1050.