I have been to all of them as i have lived in Warsaw for nearly 18 years on and off.
I can say the same and prefer other places.
You should admire people who have succeeded not put them down.
I've done quite well myself in business by understanding quality and value. At the Gessler places, value and taste sadly lag behind others in the same price range. She established the brand when there was very little competition - now people's expectations are higher and Gessler places just leave people feeling disappointed.
MacDonald's have "succeeded" too but I wouldn't recommend eating there.
It does seem like someone has a vested interest...