Parallels Deskop 7 slowness

Yes another article about parallels desktop slowness
Since I long ago updated from older parallels version to 7, it seems it has become slower and slower.
When I boot Parallels my Mac grinds to a halt for several minutes.

Last week I tried another solution to cope with problem.
I noticed spotlight was indexing while booting Parallels, of course this isn't a nice situation.

I've read that spotlight makes use of importer-plugins to index the data.
To view the executed importer you can use the following command

mdimport -L

Which results in a big list with:

2013-09-18 10:53:42.292 mdimport[5667:707] Paths: id(501) (
    "/Library/Spotlight/iBooksAuthor.mdimporter",
    "/Library/Spotlight/ParallelsMD.mdimporter",
    "/Library/Spotlight/iWork.mdimporter",
    "/System/Library/Spotlight/Application.mdimporter",
    "/System/Library/Spotlight/Audio.mdimporter",
    ...
    "/System/Library/Spotlight/Automator.mdimporter",
    "/System/Library/Spotlight/SystemPrefs.mdimporter",
    "/System/Library/Spotlight/vCard.mdimporter",
    "/Applications/Xcode.app/Contents/Library/Spotlight/uuid.mdimporter",
    "/Applications/Evernote.app/Contents/Library/Spotlight/EvernoteSpotlightImporter.mdimporter"
)

I noticed a ParallelsMD.mdimporter. WTF, I don't want indexed parallels disks.
Also I read there should be an option in the parallels virtual machine configuration to enable or disable spotlight on a virtual Machine. I couldn't find this option...
Could it be that my Parallels importer is enabled from an older parallels installation and that I cannot disable it anymore?

So I simply removed the importer:

sudo rm /Library/Spotlight/ParallelsMD.mdimporter

Problem solved?
After testing unfortunately no.. The slowness of Parallels remains.
Though it seems my spotlight indexing has improved.
It doesn't take that long anymore.