Virtualization for Mac os — what to choose?

Chose Parallels set 6 version, compared to the 3rd version is a huge difference :)

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.
\r
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 :)

VMware.
1. Reliable — has never caused a failure of the main system. (The Parallels would hang the machine into a gray screen)
2. Support for non-Windows at a height
3. Compatibility — dev vmware, you can easily migrate between Linux/Windows/Mac/server environment (ESX/ESXi).

If you need to run Windows Parallel. Good integration with Mac/Windows, invisible mode (when Parallels themselves are nowhere to be found — only applications for Windows). Well, in Depape (other dealers also have) you can buy OEM-supplythat is cheaper than the normal box (and on the website, too).
KP did not catch the 4th version :)

Actually, en.wikipedia.org/wiki/Comparison_of_VMware_Fusion_and_Parallels_Desktop there are benchmarks, and compare features.
\r
In tests of Parallels 5, Fusion 3 is the first essentially wins. On average, ~10% when working with office software, ~50%, ~30% in the speed of launching applications, ~30% in the speed of working with files.
\r
New Parallels seems more nimble in toys with regard to office work I have a difference in speed between Parallels 6 and Parallels 5 did not notice.

Start with VirtualBox if something is not acceptable then think about something else

I'm on a Hackintosh used Parallels, worked very quickly, I loved the Inline mode.