Welcome to the home of m4/3rds Rolf!
With a Leica R to m4/3rds adapter, and the E-P2 stabilisation + high res EVF - you would have a wonderful, relatively quiet system for concert photography...
I use a Hexanon 135mm f2.5 for this kind of thing, and it does a superb job.
Thanks a lot for your advice.
I like to get information, based on experience.
So the E-P2 is going to be my choice.
Last point to be solved:
Do I have to put up with the 14-42mm lens for a wide-angle solution, or is there some older glass to be found, that would deliver around 30mm.
For telephoto-lenses I am well stocked with factor 2X
Rolf re-note http://www.re-note.de