To be more general, RSUs are preferable if the stock goes up higher relative to other investments that the grantee could have picked, and cash is preferable if the stock performs worse than other investments that the grantee could have picked. For example, if the stock rises but performs worse than an index fund, then the grantee would have been better served to have gotten cash and put it into a no-effort index fund. If the grantee has an aptitude for stock picking, the balance sways even more towards cash being preferable.