At the end I’ve ended up using clusterssh

Simple to use:

cssh root@host1 root@host2 root@host3

You will get 4 windows. One for each host and a small input windows. Whatever you type in that windows will be sent to the other windows. Simple? Thats right. You can start top, vi, tail -f, … You can also select only some hosts to forward the commands only to subset of them. You can alwas click inside a terminal and use it as a normal one without the cssh features.

Try it and have fun with it.

For a less gui expirience you might want to look at pssh