I've been using this for a week now. I've went swimming with it twice and so far have not experienced any problems with the product.
It's light and pretty comfortable to wear. I have not noticed any water leakage either. I've swam all the way to the bottom of my pool with it on and my pool is around 6-6.5 feet deep. The manufacturer claims that it can go all the way up to 32 feet deep, but I was not able to attest for this.
The one thing I think that could use some improvement is the armband. It's kind of finicky to get on your arm and tighten, but maybe I was using it wrong, I'm not sure. The armband wouldn't be a deal breaker for me, but if it was a bit easier to tighten and get on my arm, then it would be a definite step up.
It is also fully touch screen usable while it is in the armband and I didn't have any problems with that either.
It is also dust proof, shockproof, and impact resistant.
I believe the case that you put the phone in is silicone rubber which would explain it's electrical resistance.
I was not able to test how resistant it was to impact and drops. I imagine only short drops that it would be able to protect it, as it's pretty thin.
Overall, I liked this product a lot and am looking forward to the next product AquaJam releases.
Here is where you can buy this product and more from AquaJam - http://www.AquaJam.com/
I received this product for my honest, unbiased, and fair review.