The design itself is good but 2 changes I would have done are sewing a loop on the back instead of using a clip as I find they can come off and with a phone that expensive, you don't want to loose it and second, I would have wet it all down then wrapped the phone in a plastic bag and placed it inside so it would mold to the phone. If you do it now though, you may loose some detail on your stamping. As far as the saddle stitch, it is about the strongest, otherwise, saddle makers wouldn't be using it for as long as they did. The Aussie leather conditioner is more for hot/cold dry areas so it may be all you need since you are in Australia. And it does say it waterproofs so it does sound like what you are looking for.