Those pistons got a bad rep for the same reason a lot of new technology got a bad rep - people don't understand it.
The goal was to find a piston material that was stronger than cast alum but less expensive and with less expansion than a forged piston. Life's full of trade offs. It's definatley a step above a stock replacement part. It can take moderate to high cylinder pressures and moderatly high rpm's for long periods of time. But they can't handle true racing abuse, and can't handle power adders.
There are also some special ring set up specs that you need to know during assembly. Failure to follow those specs results in bad stuff happening. Who is the average shadetree mechanic going to blame? The new part? Or his own skill level?
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