Subsequent reissues often suffer from a decline in quality due to mould degradation - it's what happens when you re-use the same cast over and over again. Sometimes HasTak will retool moulds to "repair" the degradation, although this is of course costly.
TakaraTOMY recently did this with Encore Jazz. The Jazz reissue mould was made from the G2 Jazz mould. The G2 Jazz mould already had degradation of the mouth (afaik the Classic Jazz reissue (which predates G2) didn't have this). The TFC and Commemorative reissues had further degradation of the mouth, giving Jazz his "sh*t-eating grin". The mould has since been retooled for Encore Jazz so that he no longer has that grin and has a more G1-accurate looking mouth.
And um... yeah...
Commemorative Ratchet?! Are you talking about Collector's Edition Ratchet? (the e-Hobby exclusive reissue that came with Ironhide)


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