Just off of Wind Surf yesterday.
There were three packages available priced by the amount of data used - one for very limited access (mainly email), the second package slightly more robust to include posting pictures etc., and an unlimited package. Speed did not seem to be an issue (not 'lightning fast', but adequate).
However, they do block access to some sites. Facebook is not blocked, not sure about Zoom and no streaming. DH purchased the unlimited package because his work requires him to monitor several forums and then found out those sites were blocked. As was DropBox and Google Docs.
If you have specific sites that you need, ask before you purchase.