I used to use a Remote Angel, which is very similar to the M1 - might even be the same unit with a different badge.
It worked fine, but was quite limited.
The buttons can't be altered - all you can do is hide unused ones.
It isn't programmable, you have to learn all the commands from the original remotes.
It has no hard buttons at all, only the touch screen. This means that you have to look at the screen to see where to press - a real pain for changing volume, etc.
In it's day (mine's about 10 years old, cost me £80), it was a very advanced remote, but things have moved on.
You might be better off getting a Harmony. I use a Marantz RC9200 these days, but that's in a different league - over £600.
