Why Juce windows are so slow?

After some time working with Juce, I noticed, that its windows move and repaint apparently slower than usual windows in Win32, what is especially obvious when u use Juce’s VST component. Is it fixable or it’s some necessary evil due to internal Juce architecture? Maybe there were already some threads on this that I can be pointed to?

Try turning off the drop shadow and transparency features in the heavyweight peer (the flags in addToDesktop)

Hey, it seems to work way faster without the shadow. Thanks for the advice.