A few comments:

1) Sign up for cryonics now. Do not delay because you think "Plastination might be better someday in the future".

• No one is offering plastination now, and you can die now.
• It's not clear when, if ever, anyone is going to offer plastination.
• It's not clear that plastination, if actually offered, will actually be better than cryonics.

2) With chemical preservation, good vascular perfusion is critical. Brain tissue which is not perfused is lost.

3) With cryopreservation, good vascular perfusion results in excellent preservation by vitrification. Brain tissue which is not perfused is still preserved.

4) Most of the costs for neuropreservation are from the up-front logistical and surgical costs. If you want minimal ischemic time and good vascular perfusion for chemical preservation you're still going to have to pay most if not all of those costs.