Are checkboxes with crosses (instead of ticks) safe to use?

Would you consider checkboxes using crosses instead of the standard ticks OK to be used in UIs?

There are several CONs (being easily confused with close or delete crosses and wrongly implying there is a "no" and a "yes" option seem to be the most severe), yet sometimes designers opt for them.

The only reason to use those I can think of is "this is sometimes the way you do it on paper", which might be a reason to opt for crosses in a UI where you are trying to replicate the look of a paper form, as a visual gimmick.