To version 5 of Parallels video VmWare performance went along. Then Parallels sharply stepped forward. When I last compared, not only was he faster, he was much faster.
In the 6th Parallels added all sorts of nice chips, such as support for Expose and Space in a virtual machine handy, you can use the application on different virtual tables to take away and switch the usual way. On VmWare now even do not want to watch :)