[TOY] Question about re-issue Transformers

I am wondering how good the G1 re-issue Transformers are.  I see them
on Ebay quite often, and am interested in Optimus Prime (I never owned
him back in the day).  I have heard some of them are not quite
identical to the originals.  I seem to remember reading something
about the re-issue Starscream having some problems.  Is there anything
to this?  If they are as good as the originals, I have no problem with
a re-issue, but if not...