Posted 7/15/2013 6:13 PM (GMT -7)
There's a balancing act... your skin gets "dirty", sloughing off dead skin cells and releasing oils and stuff, even when it's under the wafer, so it's good to remove the wafer and wipe it down (just plain water is fine) at regular intervals. On the flipside of the coin, as summerstorm said it's not good to change too frequently because often removing the adhesive can remove the top layer of skin with it and cause a little irritation.
I would say only you can know what's best for you. I believe that some of the manufacturers' instructions with extended wear flanges indicate up to 10 days of wear, so someone out there who has tested these things thinks that's OK.