I was for a very long time a tabs supporter and hold out. In fact, this is taken verbatim from my .emacs

    (setq-default indent-tabs-mode nil) ;; The Death of a Legend!

I gave up not because anyone had any particularly good arguments, but just because it felt like I was constantly fighting an uphill battle. And now that I've stopped using tabs, I haven't really thought about it for years, which is a teensy bit of stress I don't have to deal with anymore.

Having said that, keep up the good fight.