Yes, I regularly tell the pump I have a 'new' sensor after 6 days. Best I have achieved is 19 days, but typically they started to give inconsistent readings at about day 10-14. When they start to fail, they have sudden 'drops' on the graph and you no longer get a smooth curve. I've found that the further ahead of the expiry date they are, the longer they last. I am very careful about making sure the site is clean and scrubbed with antiseptic before I insert any sensor and I also use IV3000 patches to keep them stuck in place through sport and showers etc.