Wow, thanks everyone for your encouragement! Here is my scoop on COS for those who asked for it:
The first time I went into COS, I think I walked right out because the abundance of oversized shapes and solid colors didn't catch my fancy at all.
However, I often pass by the store on the way to other stores and started wandering in. The fabrics are substantial and feel so "rich", the look is modern and yet "mature", and the whole store seems to buck the trends and follow its own design logic. It's not hard to find unique pieces in COS. I would say that the quality is comparable to J Crew and Banana Republic, but perhaps a little more consistent. The colors range from neutral to vibrant, like Angie and bonnie show in their posts. And I especially love that the winter fabrics are true, warm winter fabrics: thick wool, substantial ponte, tight knits.
COS regular prices are too high for my budget (like BR and JC), but the sales are fabulous and completely within my range. Most of the store is 50% off in January and July where I live.
My main challenge continue to be fit, since I'm on the small and skinny side. COS would be a goldmine for someone at least 5`6 tall. A lot of the skirts and dresses fall below the knee, but for me it is mid-shin or almost to the ankle and doesn't look as nice. The sweaters and jackets tend to have ample sleeves or long lengths that look twice as big on short little me. There are no petite sizes. Notwithstanding, I can still get into most of the XS knitwear, some of the more "tailored" pieces like shirts and shirtdresses, and of course all the scarves and accesories.
I completely agree with those who say that trying on the clothes first is necessary. And I was lucky to have a friend with me for a second opinion. It's good to have a second opinion along when you're trying to break out of your regular style. I think I took maybe 12 garments with me into the try-on room and ended up buying 2: the dress for 37 euros ($43) and the chenille sweater for 35 euros ($40). Not bad. My friend, who is very picky, tried on two skirts and took home one. It was a gorgeous, paperbag waist skirt in aubergine wool for 35 euros. She plans to wear it for both casual and special events.
I hope you can all get to a COS sometime and try it out. I will definitely be back for the summer sales!