Gee Tom, putting anything in but good speakers means you will just blow  them 
out when you want to crank the volume.
Since the stereo puts out 120 watts rms (per channel/speaker), you will  want 
a speaker that will handle that much. I got a new catalog from Overton's  the 
other day and they have a great selection of speakers. Stay away from the  
West Marine brand, they really are terrible. The amount of juice you use will  
increase as you crank the volume, but what the heck, if that becomes a problem, 
 do like I did and add a second battery just for the stereo. :)
 
 
 
Rummy