Toyota Repair: Matrix, design flaw, regarding this problem

Question
QUESTION: I asked you the question about my Matrix going from 4th and 5th
into neutral Your response was worn parts

What would you suggest Rebuild it There is some indication of
the matrix transmissions having a design flaw during that timw

ANSWER: What year is the matrix and how many miles on it?

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QUESTION: It is an 04 with 80 thousand miles

Answer
Ok thanks for the reply, it's out of warranty so it really doesn't matter if there was a "design flaw" which I'm not aware of and there are no service bulletins regarding this problem. These transmissions have to be completely disassembled to replace anything internally which means most of the cost is going to be labor, have you considered getting a good used transmission?