Yes they are, and so are ribbons. The problem is not so much in the type of music...but the quality of the recordings. A great deal of rock recordings were recorded (lots of compression) to sound loud only. These types of speakers are not forgiving of poor recording quality, they will sound very, very good with rock recordings of high quality. The other problem is that most rock music has a foundation which is built on bass, cost of full range e-stats or ribbons can be high and a good sub that will blend with them is also a cost. If cost is of no matter to you and most of your rock is of higher quality recordings...you should be very happy. IMHO
Dave
Dave