I think part of the problem is that the RS4 was received with so much praise because no one expected Audi to trump the M3, as Audi generally don't make drivers cars and for that reason expectations may have been a little low for the RS4. This combined with the fact that the R8 was, again, a great handling car meant that expectations for the RS6 were always going to be high. So far it hasn't seemed to live up to these inflated expectations.