If I remember right the chance of it rescuing you were estimated to be somewhere between 10-20% by senior LessWrong people in the last census.

The interesting thing was that senior LessWronger were more likely to recommend people to undergo cryonics then less senior people when both believed in the same probability of being revived.

In the end the question is:
p(getting revived) * u(utility of getting revived) <? u(utility cost of acor payments)