Thoughts about exactly what aspect of them? Personally, I think they're an okay casting (not great), but I believe the stock valvetrain components suck.
Of course, I have no first hand experience with them, so those are just my personal opinions, which I have based on what other people have stated. But, I have read many people say the same thing, and some are decently knowledgeable. Take it for what it's worth.
'94 Laser red 'vert. Still a 5-oh... for now