I recently got an assortment of these Eagle Creek packing cubes and folders for a 3 week trip to Europe.  At first I thought this size was going to be too small, but I ended up liking it much better tha the larger size that I also ordered.  I have 2, and used one for my tops, and one for my pants and shorts.  I was able to get over 12 shirts into it - mostly Tshirts, but, but it was fairly roomy when you rolled the shirts.  It also fit 4 pairs of shorts, 2 yoga pants, and a pair of jeans.  AND, I'm a size 14, so they weren't tiny clothes, either!  For both the shirts and pants, everything remained remarkably free of wrikles.  As other people have mentioned, the more you put into these, the better for keeping things neat, which seems contrary to how it works.  For a size trip that my fiance and I took to Venice, we wanted to share one small bag, so I managed to get 3 days worth of clothes, and extra dress and pajamas into one cube, and just toss the entire thing into the small suitcase.  His stuff ended up taking WAY more room than mine, and my things were far more organized.  Since we are normally the other way around, he was really impressed.  I'm planning on getting him is own set up cubes so that we can share bags, but still stay orgaized in the future.