Since this is my first down jacket ever! I have a question about storing it away for non-winter months. Is it okay to compress it in its own sack and store is for 5-6 months? Does doing that ruin the feathers inside? scrunch the feathers?

Closet space is something I don't have much of...so, I keep all of my down jackets and hats stored inside a large Rubbermaid tote uncompressed.I keep my down bags stored loosely inside the cotton storage sacks.

Of course hanging is the answer. Have MANY down jackets that are hung in the closet with care like a Christmas stocking. I keep all down hanging and sleeping bags as loosely stuffed into there oversized bags as possible.

I would never consider storing any down product compressed. Down gets a lot of warmth from loft and this will be compromised by storing compressed for long periods. Precisely why many quality sleeping bags come with 2 bags. One for compressing while out and another to store loosely at home.

I would not store it for long periods in its stuff sack; it can damage the feathers. You should just store it as you would a normal jacket - on a hanger in the closet. No real need to treat it differently. The stuff sack is primarily for packing it small for short periods of time in a backpack for backcountry use or while travelling.

It's always better to store any down product uncompressed on a long-term basis. Yes, it's not good for the feathers. Just hang it in the closet.