You must be able to see the Omnipod (the pod) for the remote (the PDM) to connect to it. Range is 6ft max and, if you don't have clear air/just clothes between the pod and the PDM it can drop to as little as 3ft.
Uploading the Omnipod data is extremely difficult and unreliable, it's not the pod; the problem is that you need a piece of software (the Abbott Copilot software) to decode the data and that software is extremely unreliable. I gave up using it so I have no recent experiences, they might have fixed it but Abbott/Insulet didn't show any inclination to address the problems in the past.
You can see the PDM screen fine in sunlight; the PDM has a 'light' button and if you hold it down it ramps up the brightness. I've never had any problems on the beach with a little bit of shade (just a hand or my own body.)
I don't have any problems with the pod adhesive, it just works even if it is exposed to water continuously. The only time I've ever had it stop working is while exercising continuously (lifting 90lb bags of cement) and, therefore, sweating continuously. Eventually the pod got loose. Other people, however, do report problems with exercise and use stuff like tegaderm as a secondary means of securing the pod. I think it depends how fit you are, your daughter is likely to be very fit, being 8, and therefore probably won't have any problem. (Very fit people don't sweat much under normal conditions.)
I don't know what the Ping interface is like, but the UI to the PDM sucks. It may just be the general state of medical devices, but it requires numerous 'ok' button presses which inevitably leads to me not even reading the screen once I know the sequence.
The FreeStyle meter has had major problems in the past; it is absolutely essential to get the latest test strips with an expiry date later than July of this year. Some US pharmacists still have stocks of the old ones. You just have to be very careful; I stopped using Walmart because they just kept giving me the unreliable ones, but Walgreens, despite having an almost identical name, have been perfect.
The pump is pretty much unconditionally waterproof. I've seen exactly one fail under pressure; I suspect there was a manufacturing error, but I was using the pump way outside the Insulet limits. If your daughter swims then the pod is pretty much the only choice; the Ping is only rated for 9ft submersion and it is really easy to exceed that in a swimming pool, or when snorkeling. It's almost impossible to exceed the 25ft rating of the pod.
There have been insertion problems recently. Very rarely a pod will not actually insert. I've had two or three occurrences of this, I just flicked the pod with my finger and it inserted. Other people have reported partial insertions - the steel needle goes in but doesn't withdraw causing some amount of pain - these seem to be fixable with the finger flick as well.
The PDM carbohydrate algorithm is extremely crude. This leads to problems of underbolusing corrections after a meal; the PDM falsely assumes that the meal is absorbed almost instantly. This can be fixed partially by lowering the PDM setting for insulin duration, but then this creates an inverse problem with over corrections when a meal hasn't been consumed within the last few hours. Changing from the Ping might require very significantly different settings on the PDM and you would need to watch blood glucose very carefully at first. Expect to see post-prandial highs initially.