FWIW, FX is not being made anymore. "Mr. FX" has upgraded the molds and now uses the AM brand to differentiate them. Any FX suits you see that are new are either recast or from someone's garage that they never completed.
AM addresses several of the inaccuracies of the old FX, notably larger bucks to help close the side gaps, correct ab plate buttons, and split butt plate.
The FX helmet is still being made, but it being a bit large for most people along with being the least accurate in appearance has led it to be deprecated, especially as more accurate helmets have really come down in price.