Both make great engines. Can't really go wrong with either. I tend to believe that DA offers better service than 3W. I have my reasons, but I just leave it with you as my opinion. Oops, no opinions. OK, had a buddy send in a 3W150 and a DA150 for "service". Both were about the same age and needed similar work. 3W service center charged several hundred dollars, which was fair, but DA didn't charge a penny.