Homer, do you not realize that you regularly use this antithesis argument in a way that only makes your point when using aionios to mean "endless"?Perhaps its just me but you seem rather irate in your post. I have made no statement about the meaning of aionios in general, so why the outburst about there being no excuse for my ignorance?
The antithesis argument is that the word must mean the same thing in its two uses in the antithesis. No one denies this. The only way it can be used to make your point against restorationism would be if you are insisting that aionios means "endless" in both appearances in Matthew 25:46. In other words, your argument, to be cogent, depends on the necessity of aionios meaning endless.
Since I assume that you know that this is only one of several possible meanings of aionios, it would seem disingenuous to make an argument that depends entirely upon this knowingly false assumption of the meaning. It has been pointed out numerous times that, if the word means "long-enduring" (as is most commonly suggested by modern Greek scholars), it would comfortably bear this meaning in both of its appearances in the verse. Thus, both the life and the punishment could be said to be "long-enduring" without any hint that they are equally long-enduring. I made this point in my book. You are welcome to try to refute it, if you think it possible.
Also, if the word aionios means "pertaining to the age" of the Messiah, as many evangelicals, including F.F. Bruce have argued, then it can equally apply to the life and to the punishment without a hint concerning the duration of either.
Unless one insists (ignorantly) that aionios must primarily or exclusively mean "unending," the argument which you have repeatedly made from Matthew 25:46 has no force whatsoever.
It also is not helpful to your point to keep emphasizing the fact that aionios was Matthew's translation of Jesus' words from the Aramaic. Unless we are doubting that Matthew used the proper word to translate Christ's words, the case concerning aionios remains unchanged.
In the Septuagint, the Hebrew word most commonly translated with aionios was olam. It is likely that Jesus used the word olam, and that Matthew, following common translational conventions, rendered it with aionios. But olam has a range of meaning similar to that of aionios (which is why the LXX translators made the translational choice to use aion and aionios to translate it). It means a very long time, which can include forever, but needn't.