The Plus score has a range of 330 to 830 and the Vantage score has a range of 501 to 990, which would imply the Vantage score will usually be significantly higher. In addition, the formulas for each model are different - if I remember correctly, I believe the Vantage score does not factor AU accounts when scoring.
Your best attempt to estimate your EX Fico score would probably be to take your EQ and/or TU Fico score(s) and compare the corresponding credit reports. If one of the reports is nearly identical to your EX report, there is a reasonable chance your EX Fico will be somewhat similar to the corresponding CRA's Fico score. But it only takes a few differences between reports to cause noticeable score differences ...
