I have an old Saito 65 GK in mine (kit) and had to move the the radio stuff to the back of the cabin to balance it. Maybe the ARFs are tail heavy, but mine isn't. The 65 is really a bit much for this plane, but was sitting there when I went to the shelf looking for an engine. Not sure why anyone would overpower one of these, except for a giggle maybe. Lots of fun to fly a three channel floater.

Steve