1% DOA would actually be pretty high, the majority of failures in consumer electronics occur after 3 years (the 15% you're talking about), in the first year you're typically looking at 3%-4%. For DOA, anything over 0.85% is considered well above average.
However, building consumer electronics is an iterative process, unless there is a major design flaw which is too expensive to fix or a particularly problematic critical component, they'll iron it out relatively quickly.
While i agree that it might be a pretty high % for DOA, one could argue that it is much better to have units malfunction immediatly instead of mass malfunctioning after a period of time (RROD).
I think Sony will be just fine.