Greg Eiseman wrote a review of Stoic WPF Compression Sack on November 1, 2013
Familiarity: I've put it through the wringer
I was "on call" at work and there was a big swell. I didn't want to just sit at home when there was waves so I through my iPhone in this bad boy, stuffed it in my wetsuit and hit it up. After surfing for 2 hours (and not getting called in) I went back to the car.
Opening up the dry bag, I noticed there was some condensation on the inside of the bag and my phone was pretty wet but still working. Thank goodness!
When I got home I through my phone in a bag with my scrubs in it to carry everything inside. When I looked in the bag, I found that I had thrown my phone in a yogurt that had blown up from the heat of the car. The yogurt plugged up the headphone jack and the phone stopped working. It survived getting moist in the bag only to get ruined by yogurt! After a week it did start working again!
Sack isn't %100 waterproof