I've been using Medtronic CGMS on and off since 2007. Now I'm making the jump to Dexcom tomorrow hoping for a larger range and improved accuracy. I have two questions. 1. Does the Dexcom let you set different ranges for day and night? Or different time periods? I like knowing if I'm going about 170 during the day, but don't like being woken up until 250 at night. 2. Can you silence alerts for a set time period? Sometimes I get a bunch of false low alarms and this is the only way to stop me from throwing it out the window.