"Put it simple, it works as it claims. I also live in the Chicago area and winter weather here can be hectic. The stretto humidifier manages to maintain the RH of my violin case at about 60 when closed. I also use distilled water. The instruction says 3 minutes of soaking, but I usually soak the pack for 10 minutes. A gallon bottle of distilled water )about US$0.80( will be more than enough for the whole winter. The provided velcro does not stick to the interior lining of my case. Turns out I ventured to use the iron-on velcro for clothing )available @ Walmart for about US$4.00(and it works very well. Since I have no access to the back of the material, I simply place a terry-cloth towel on top of the velcro and iron the velcro with steam on."