Depends on what you're after. I went with the Akra because I like the sound and have no tolerance for drone. The Eisenmann comes in a tame street version or a really loud race version. I know a guy with the race version and I can hear him a mile away. I've also seen some problems with the finish flaking off of the Eisenmann's - not sure if that has been addressed or not. This is not much of a concern with the natural ti finish of the Akra.
Another thing to consider is resale value. I don't think you'll have any trouble selling an Akra if you ever decide to cross that road.