Ernie Ball 2921 M-Steel

Maybe I should wait a little longer to write this feedback. I have only used two sets of them yet...
I seem to have acid fingers. Standard strings lose their tone i about two or three hours playing. Therefore I have used Elixir Nanoweb for many, many years and I have liked them and still do.
But these Ernie Ball M-Steel has something special. They have a power, a force and a stringy clarity that I like. They don't go dead nearly as fast as standard strings but are not as good in this as the Elixir Nanowebs.
I have to decide if it's worth to change strings more often than with the Elixirs, but the tone of these is really good...