The same logic applies for HD-DVD and Blu-Ray - If the quality of the SACD or DVD-A isn't enough to get the average consumer to buy it (audiophiles only)- Then why would they buy HD or Blu-Ray? It will fail too.
So, it will be a loooooong wait for the next hi-rez format if there ever is one.
So, it will be a loooooong wait for the next hi-rez format if there ever is one.