There is no answer to that that can be agreed on. Im sure we have all seen the threads about this very thing.. ARF crash's and the owner posts all about how it was everything but his own fault.

Most ARF companies I am aware of have liability definitions that basically puts the owner at his/her own risk, beyond the most obvious of manufacturing flaw's/defects, and even that will only hold up if the plane is within its assembly state, prior to flight anyways.

Bottom line is, or rule of thumb.. you (the owner) are responsible to assemble the airplane to be airworthy, period. The manufacturer really only claims that the airplane is capable of flight.

Of course, this is just a point of view, and may not necessarily even completely factual or accurate, for all I know.