Preview film strips super slow from the dock preview..

[MRequalsMC]

Not sure about you guys, but I am experiencing serious lag when I click on download folder (which includes) small jpg's, video files, or miscellaneous png's. When I use the same process to view pictures (5-6mb) from the dock, the preview works seamlessly. For some odd reason its Download folder that is the issue, and not only the pic or movie clips but also icons (MS Excel icon). I have to literally have the window open for 30 seconds until all of them appear. Few minutes later, when I go back and preview it again, the same process starts over again. I should mention that the only one film strip will be already there, at the time of actuallyl clicking on the folder. Also, I am running a 250gb solid state, so speed of Hd cannot be a issue here. Anyone else experiencing this?