Disklavier

I am considering trading my DC3A disklavier for a DC3M4t disklavier.  I 
have not yet been able to see or play a DC3M4t and so I have two 
concerns that can be answered by anyone who owns a Mark IV disklavier.

 (1) The Mark III disklaviers like my DC3A have two 60 watt speakers 
mounted under the piano firing straight downward. .  The DC3M4t has two 
20 watt speakers mounted at an angle so as to deflect ensemble sounds 
outward from the piano  There is a significant difference in the power 
rating of the speakers (60 watt vs. 20 watt) between the Mark III and 
Mark IV disklaviers.  Can you tell me if you are able to get the Mark IV 
disklaviers to play ensemble sounds sufficiently loudly to balance the 
volume of the ensemble sounds against the acoustic piano? 

(2) I understand that the input/output center of the Mark IV disklavier 
includes at least one USB port.  However, from Yamaha's specifications 
for the Mark IV I cannot tell if this is a USB 2.0 or USB 1.0 (much 
slower speed) port.  Can someone who owns a Mark IV tell me if the USB 
port is 2.0. On their web site, Yamaha states that "Certain USB storage 
devices may not function properly with the Disklavier Mark IV series.  
For a list of compatible products, please visit 
www.yamaha.com/disklavier."  However, I cannot find any such list of USB 
compatible storage devices.  Has any owner of a Mark IV disklavier 
attempted to attach an external USB drive to the Mark IV's I/O center?  
Did it work properly?

Thanks in advance to any Mark IV owner who can respond to these questions. 

Tom