Yamaha DTXpress/DTXplorer/DTXtreme

I am buying a DTXpress.  I assume that I need to buy an amplifier or 
monitor with it.  I would like it to be able to achieve the volume of 
a standard drum kit.

I also would use the amplifier separately as an electric guitar amp a 
small portion of the time.  (I don't need much volume - about enough 
to go with a standard drum kit - or less).

Any thoughts?  Also - would anyone buy a different electronic drum 
kit if they had it to do over again (It seems to me that for the 
price, the DTXpress can't be beat).

Don Pulitzer