Slow WPMU performance (http get 200 ok)

Does anyone know why my site has an http get 200 ok time of almost 1,8s waiting?

And why does the site still refers to my parent site? (letuslook.nl)

check: http://tools.pingdom.com/?url=http://www.krediet-informatie.com&treeview=0&column=objectID&order=1&type=0&save=true

I hope someone is able to help me!

Thanks,

~ Luc