Voted for "WITH KEYBOARD".
This doesn't mean for me that a keyboard is a absolute must for a rockband, but some bands I like use them and I never found it annoying really. In most things I know they're well integrated in the sound.
Also I have no problems with a keyboard on stage. Guns 'N Roses are a good example for me that it wasn't disturbing to have a keyboard on stage. Same goes for D.T.R (though what I've heard from their live video, Kenji is pretty much hidden in the background). Another example could be Rammstein. Rammstein without Christian "Flake" Lorenz would be much more boring in my opinion!
(Not a Rammstein fan, but Flake rules! What a freak! XD)
I wouldn't count X to that range. It's a piano and live drums and piano never have been played at the same time naturally (if so :arrow: one of the instruments = playback :arrow: I don't count it to live really
).
As for guitar-like keyboard vs. normal keyboard: I really prefer the normal ones. Of course the keyboard player cannot move much then, but those... strap-on keyboards (sorry :twisted:) simply remind me too much of:
In case you don't know them, click on the pic to see video - WARNING: Watch at your own risk! :twisted: