My doctor who is a diabetic, told me to get Tincture of Benzoin to keep my Dexcom stuck and it will stay on for 2 weeks! I take it off with Unisolve. It’s cheap, kind of a brown looking color when you put it on a cotton pad but you swipe it on your skin, wait 5 minutes until you feel it’s sticky, sick on the pod or sensor and it really sticks. I also found swabs on drugstore.com I think, that work really easy but the bottle of stuff is so cheap, like $3 and lasts a long time. I am waiting for my omnipod but used Tincture of Benzoin with my sample and it had no trouble staying on my side.
Is that also good if you are going to be in the water a lot?
Absolutely and that was the primary reason the doctor recommended it. We went to Mexico for 2 weeks and were in the pool/ocean every day and for hours. About 5 days in, i had to put a little more around the edges then stuck it down again. My sensor lasted the entire time. Here are the swabs I got off amazon. They work great an are easy to use. Doc said hospitals use it for patients IV’s etc to make sure they stick.
http://www.amazon.com/PDI-s42450-Benzoin-Tincture-Swabsticks/dp/B0015TER90/ref=sr_1_3?ie=UTF8&s=hpc&qid=1273241243&sr=1-3
I will have to get some and try it. I tried the Arrid extra dry and that is holding for now, but i can feel that I am going to need something more. I am in Florida and have to deal with the humidity and the heat. I am going to see if my local pharmacy has it in stock or if they can get it in for me. If not, I will get it off the link you provided.
FYI - Mexico was wicked humid for us (we are from Seattle) and we did some canopy tours and sweated a ton. No problem at all.
I use alcohol to clean the skin and SkinTack to keep it in place during the hot sweaty months. Otherwise just cleaning the area with alcohol first works just fine for me! 
I use Skin Tac to prepare the skin before I put on the pod. If you have problems with the pod coming off the adhesive backing, then I would get IV3000 adhesive patches to tac the pod to the adhesive patch or to just put over the pod and adhesive patch. It’s very sticky and stays on at least a week.You can also buy Nexcare tape at Walmart and most drug stores. They make a water-proof tape that should keep the pod attached to the adhesive patch. I would also buy some Unisolve patches to get the Pods off more easily (you can order online).