This is very easy and is not a big decision!
If you are used to wearing orthotics or other supportive shoes and sandals, then it is likely that you will prefer the feel of our of high arch support model.
If you are not used to wearing orthotics or supportive footwear, then our standard arch model will likely be a better choice for you.
If you have low arches / flat feet, then you will likely prefer our standard arch model, as the high arch support will likely feel that it has too much support (unless of course you are used to wearing orthotics with a lot of support).
If you have high or normal type arches, then you will be fine in either our high arch support model or our standard arch support model, it would just come down to personal preference of what you are used to and your support needs.