It makes the phone a little thicker, but I really don't care about that since I carry my phone in my purse or leave it sit on the table. So far, it seems to be a great thing. It is a little slick, which is bad for me since I drop things all the time. But, in the last 3 weeks, I haven't dropped it and the battery hasn't died in the middle of the day.
So this is my plug for a great item! If you have an iphone, buy it!
And one more thing, the adapter you use with the iphone to charge the battery is pretty bad. I've had to buy 2 since I got the phone (which is only one year now) because the wire becomes exposed at the base of the connector. Before you tell me I'm hard on the cable, I will tell you that I am not! It just sits there and charges. The cable that comes with this case is much stronger! I figure, If I would have bought this months ago, it could have saved me from buying the other cords which would have almost paid for the case!