A suit bag is essential if you are looking to store in style. Keeping your clothing protected is key to long life and looking good!
Oftentimes you will get a bag or plastic zip up piece to go with your new suit. These can be used temporarily but long term usually aren’t a good deal as they generally aren’t breathable. Those nylon bags are OK for storing on a short trip though, or packed in a suitcase for example. They’ll offer some protection. For hanging in your closet long term, they’re not the best idea. They can break down and produce chemicals that can damage your suit.
In most cases, you should use a cloth fabric bag. This will prevent the fabrics from rubbing against each other and unwanted pinholes and tears on your expensive suits.
Cotton or canvas tend to work the best as it protects but also allows the clothing to “breath”. Plastic tends to hold odors and moisture and traps the air near the suit, sometimes leaving a stale smell. The plastic ones with a canvas or cotton backing are ok, as they still allow for some circulation. They’re also nice because you can actually see which suit is in there, without unzipping a bunch of bags at a time.
You can get bags that will work for a couple bucks at Wal-Mart or Amazon. That’s usually just a basic plastic/canvas combination. If you’re in a pinch, you can make your own out of old sheets, bed spreads, or pillow cases.
The top of the line suit bag would be one using cotton muslin. These are the same material that museums use on their preserved clothing so you know its good. The hangar will be totally padded as well. Expect to pay up to $35 a pop for one of these. However, if you have a $50000 Kiton then obviously putting some money into the right bag is a worthwhile investment.